My very limited experience says that it is important to have a schedule, for a regular practice, and a set of asanas what focus on your weaknesses. Everyone has those inbalances, maybe not that obvious until you start practicing. As in anything in life, important is to start easy, stop at half the load you’d expect from yourself, and be resilient in your practice.
I like to think that asana is the food for the body. Just as in your diet where, if you practice a discipline, you will discover the wisdom of the body, telling you what you need to eat, so it is with asana. First you need a set of them, practice them, get the benefits … but don’t forget, that this is forced. Asana practice becomes natural when you reach the point that you perform asanas you never heard of just because it comes from the inside. It’s not a miraculous thing, it is just the wisdom of the body. Look at animals, cats, dogs, horses … they do asanas without ever hearing about yoga.
So discipline, and adherence to rules is just one side of the coin. There is where you start. It is very important. It is governed at first by your usual, everyday consciousness, and yes, by your ego. It has it’s risks, that’s why a personal trainer is that helpful. Otherwise you’ll learn the hard way, like I did, that ambition is bad if it is not balanced by patience. This is something you can’t rush.
Your body is not your creation. It is part of the world, also not your creation. You don’t know what builds it, keeps it togheter every minute, what it makes it to function, and how. In fact, if we come to think about it, we don’t really know anything. I am speaking here about direct knowledge, not about having images of anatomy pictures in our minds. This is good subject for meditation. Think of yoga as a way to get direct knowledge about yourself, and you will find a reality what surpasses everything you learned.
Think when do an asana … this body. Is not me. How could it be me, if I don’t know it at all ? It is part of the world. But it is a special part … it is given to me to take care of. It is a garden and you are the gardener. Know your garden and take good care of it. By knowing yourself you’ll know the world, not like materialist science knows, disecting, analyzing and rationalizing, which is interesting but nonetheless dead information, but a knowledge of union, vibrating life and living emotion.