Try this simple exercise:

1. Stand on both your feet, as you normally do when not walking.
2. Now, keeping your body straight, try to lean very slightly to your front, as much as your feet allow it without having to make a step. You should now feel your weight resting on your toes.
3. Now, lean as much as you can towards your back. Remember, your body should not bend in any way. You should now feel your entire weight on your heels.

Maintaining your axis is a very important thing when dancing tango. In fact, you should probably concentrate most of your attention in the beginning on how to step and how to pivot while keeping your wight on the right foot.
You wouldn't want to push or pull your partner and you wouldn't want him/her to feel as trying to move a door!

This is the beauty of it all when speaking about axis. You can lean on your toes and give him/her that perfect embrace he/she's been longing for and still allow your legs to have enough room in order to make the steps, the pivots and those nice adornos you've been admiring on YouTube.
Or you can simply lean towards your back to magnify your steps, to better feel the energy and put it into your best moves.

Now don't misunderstand! During a single song, you will probably switch between the two depending on where he may lead and on how she may want to shape it. The important thing is to keep in mind that between your toes and your heels is the place you want to keep your weight and your axis. Also remember that your partner has the same range to play with when it comes to his/her axis. Therefore, the most beautiful movements will probably derive from this game you are both playing.

There will be times when you will feel that you have pushed out of this range and lose your balance. Even if this is acceptable for the first few lessons, in time, you should learn to control your body as you please! "Really?" you may ask. Well, in fact, yes! After all, it is YOUR body we are speaking of and YOU of all people should be able to control it as you please. Yes, you may lose your balance. And yes, you may not be able to make that perfect pivot from the very first lesson. But that is all probably because nobody has really explained you how to do it. In your own terms.

The key to keeping your axis is the perfect balance between the energy you are receiving and the steps you are making (together with the shape you decide to give them). For example, when talking about a voleo, you can actually pinpoint the energy rising from the leader's torso, going through his arms into the follower's arms, upper body, leg and finally all the way through to her toes, giving the beautiful shape of a voleo.

What kind of exercises can you try for maintaining your axis?

Caminar - maintain at every step your toes, your torso and your forehead on the same vertical line.
Caminar with a counter balance - work in pairs. When you are walking to the front, your partner should push you to the back. You should be able to push him back and make a step in perfect balance. When you are walking to the back, your partner should push you forward. Work until you can make steps in perfect balance. You should be able to do that by finding the equilibrium between the energy of your partner's push and the energy you invest in the movement.
Pivot to the wall - take the wall as your partner and try to make 180 degrees pivots in perfect balance. At first, you will lean towards the wall to take the energy you need. In time, you should be able to let it go more and more and finally, do the pivots on your own. After that, play with the speed of the pivots and the adornos you can do.

The second installment in our series of beginner's tips for followers. Here goes:

1. Try not to swing during the dance. Don't lift that shoulder, nor any hip. Your movement should be smooth and should not unbalance your leader. Normally, the leader shouldn't swing either, but if he does, you try to keep your balance and help his.
2. The order of things is: leader's intention -> follower's step -> leader's step. Your duty as follower is to try and feel the intention and then go with it. You will wait only if the leader wants you to wait.
3. When you make your step forward, make sure that your head, your chest and the tip of your foot align on the same vertical front. Also, when you make your step back your head, your back and you the tip of your foot should be on the same vertical line. If by any chance any of them aren't in an alignment, you will most probably break the embrace, alter your posture or simply look funny - bad funny that is!
4. Think of half tempo level. When you will get accustomed to the tango beat, it may seem too slow for you and that will only get you to think at half tempo. Doing that will allow you to make any adornos you like, tap at half time and make your dance that more interesting.
5. Think at double tempo level. When your partner leads your steps on a very slow tempo (step on 2 beats), it's a perfect opportunity for you to improve your technique. Make sure you make your steps in the right assigned place on the floor, that you don't hesitate in moving your weight, that you have a perfect posture, that you continuously maintain the embrace and so on. The slow dance is the best way to test a lot of your skills.
6. Ocho is a very useful trick that many leaders use to enter some other cool trick or a sequence of steps. Still, when it is used abundantly (that means more than 3 consecutive ochos let's say), you have all the right to be annoyed, since it's not the most comfortable step. Anyway, if you are trapped in that kind of a situation, try to work on your pivot and also, any adorno will do.
7. There will be times when your leader will simply stand still in the middle of a song. Enjoy that time and take the opportunity to better adapt your embrace and prepare the next step.
8. The leader will not always make the same steps he leads. He may also lead some steps to you while standing completely still. try to feel his intention and not his steps.
9. Try to always maintain the embrace. Don't give more space than required and don't cover more space than needed.
10. Tango music is usually composed of 8 tempo phrases. A leader should dance to the phrase and stop at the end of a song. However, if he isn't a very good listener, if you feel the song is ending and your leader is still preparing some steps, you can try to slow him down until non-movement by putting more weight into your steps. The feeling for the leader will be that you have suddenly become heavier and that will slow him down.
11. Argentine tango draws its beauty from the liberty of improvising. There is no choreography and therefore, do not expect a certain sequence of steps. Every dance will be different with every leader and with every song.

The second installment in our series of beginner's tips for leaders. Here goes:

1. Keep your shoulders on a horizontal line - don't swing during the dance (that means sideways as well as up/down). Just imagine your follower is trying to read the fine print on your T-shirt. Or - have you seen those Indian ladies carrying tea pots on their heads? That.
2. The order of things is: intention -> follower's step -> leader's step. Even though these all usually happen within half a second, you need to think of them in this order, because your reflex should not be to just walk and make your follower walk, but to make your follower walk, check if he or she did, then walk.
3. When you step forward (and you will be doing a lot of that), make sure your head, your chest and the tip of your foot are on the same vertical front. If your head goes ahead, you lean forward and we already agreed you wouldn't do that; if your foot goes first, that means your follower didn't get the intention yet, has no reason to move and you will step on her toes; if your chest goes first, you'll look like a chicken. The "vertical front" movement is the safest way to ensure that your step will fall under your body, where there's no way you might find the follower's toes.
4. Think at half tempo level. If you feel the tempo beat comes too fast and you have no time to perform your tricks, "overclock" your plan! - think in terms of half tempo, and the tempo will seem like all the time in the world
5. Think at double tempo level. It's harder to do a trick slowly, but it helps a lot. It improves your balance and your leading skills and it forces you to manage the energy better.
6. Do not abuse on the "ochos". They put an unnecessary strain on your follower and they are not a remarkable achievement by themselves. That means, at the end of two successive "ochos" there had better be a stunning trick in your plan, otherwise your follower is entitled to give you a black eye.
7. Do not abuse on the sidesteps either. You know that not very meaningful Tango trick called "standing still"? Well, sidesteps are even less meaningful. So, when in an inspiration crisis, stand still, embrace your follower fondly, make a dreamy face and wait for the next phrase to begin.
8. What you lead to the follower and what you do yourself are two different things which sometimes coincide (for symmetry). You should be able to lead any step (forward/backward/side) to your follower, while performing any of those steps or standing still - all as long as the embrace doesn't break.
9. As far as balance is concerned, you need to mind your own axis and the follower's axis, or rather her or his space. When you invade this space, the follower is in danger of losing balance and thus so are you.
10. Tango music is usually composed of 8 tempo phrases. It is nice not to tap around while a phrase ends and another begins - and it is also nice to stop walking when the music ends. Exactly when the music ends, that is. It is also nice to make a dramatic pose - exactly when the music ends.
11. Don't learn steps. Learn how to lead steps. Whenever you learn a new step or trick, practice it in various sequences, try to start it in different ways and continue it differently. Many times you will learn exercises. Don't just repeat the exercise. As soon as you get the hang of it, vary it. This will also help your followers a lot.

Here are some useful notes for a beginner leader:

1. Step straight forward in full confidence - or you will just end up doing a funny swing, thinking to avoid her feet. Now, stepping on her toes might hurt your dancing relationship, but walking like a duck will definitely kill it. Put your heel down first, and not the way you would if you wanted to kill a bug.
2. When you lead a pivot to your follower, have in mind what comes next and make sure you share that thought. A pivot is much easier if it takes the energy from the previous move
3. Keep a straight pose. Do not seek to help your follower in his or her job by bending inside their space. You will achieve the exact opposite and the couple will look dreadfully.
4. If you do want to help your follower, concentrate on keeping the information flowing in all possible sources: your arms, your upper body, your hips. If your follower can understand what you want, without being a psychic, that makes him or her comfortable
5. Your attention should be shared between your own dance plan, checking if the follower is where you expect him or her to be and checking the environment (i.e. the other pairs, the space, if the wife is looking, etc.). The first factor is up to you. Try to minimize the second and maximize the third.
6. If your follower ends up on the wrong foot (in reference to your dance plan), you have two solutions: - adapt; or -stop. It's OK to pause, adjust your embrace, reset the steps and then start again. Don't pause if you can adapt, but pause, rather than require your follower to adapt.
7. Be firm in your decision, don't hesitate. Make your steps clear and decisive, even if they are wrong. For a follower, being unable to follow what you lead is far better than not knowing what you lead. Partly because the former situation rarely ever happens. Followers are quite resourceful.
8. Never be afraid to ask someone to dance. When you ask, though, be honest about your skills and stick to what can't go wrong - particularly if you have never danced with that person before.

Here are some useful notes for a beginner follower:

1. Do not be afraid to make that back step. If you are given the energy for a big step, do go with it. Whatever you do, try not to kill that energy, since it may give you the force you need in dynamics.
2. When you pivot, make sure you do so on one foot and for starters, with your heels close together. Work on that until you get it right and then you can start playing. :)
3. Keep a straight and pleasant posture, relaxed and comfortable, yet offering some tension in the arms.
4. If you want to help your leader, be sure to make a step only if he gives you the energy for it. Try not to anticipate, but more likely to adapt.
5. If you can, try not to pin point the leader's chest. Instead, try closing the eyes to better feel the couple.
6. A leader doesn't always make the same steps as the ones he leads, so you can't dance just by looking at his feet. And neither should he just by looking at yours.
7. Whatever you do (steps, voleos, giros, ganchos, even mistakes), do so by looking great! :)
8. If you make a mistake, don't stop. A good leader will adapt to it and just go on dancing.
9. Never be afraid to accept a dance invitation. Every tango experience is good experience.

to be continued...

There will never be a step, sequence, or trick in tango that will come close to matching the power of the embrace --Ney Melo.

So, what is the point of the embrace? Well, the first answer would be that we cannot single out one point above all. But here are a few candidates:

1. To connect the partners into a new entity - "The Couple"
2. To channel information from the leader to the follower and the other way around
3. To secure the necessary space under and around the partners, in relation to the other couples dancing around
4. To generate on one side energy and on the other side comfort for the two partners
5. To socialize and make the best of your expensive perfume

In more detail ...

Here are the first 10 hints:
/TODO/ Intro ...

1. It's more about listening than it is about dancing.
2. There are three steps (just three): forwards, backwards and sideways.
3. There are two roles: leader and follower.
4. There are three Tango rhythms: the Tango (classical), the Milonga and the Tango Waltz; the "New Tango" or "Tango Nuevo" can also be seen as a separate branch.
5. Tango is usually danced in a ring, following (and respecting) a counter clockwise direction.
6. The embrace is arguably the most important feature of the dance. It can be open or closed.
7. Most of the time, Tango dancers have all their weight on one foot, whose choice is not (entirely) random.
8. There is (surprisingly) such a thing as a "basic step", or "basico".
9. There are two dancing systems - parallel and crossed.
10. There are many great teachers of Tango touring the world, from which you can learn new tricks.

And now the explanations: