This post is addressed to the first-time yoga. I hope my simple advice will be useful to start-up yoga, and more advanced practices will be shared by their thoughts and observations in the commentaries.

Those who do not need advice immediately refer to the description and scheduling of yoga classes at the Tapaz centre:
The preparatory class is recommended for those who are not familiar with yoga Ayengar and consists of several orientation sessions.
The primary class is practical for everyone, regardless of the level of training. If you're not sure of your strength, Better start. replacement class

And now practical advice:
(1) They usually practice yoga as a sausage. Of course, you don't want to come to the socks, but you won't be able to fully monitor the feeling of the foot, which is very important in the performance of many asan. Safety issues are also important - in your socks, you are more at risk of slipping on the parked floor; and even on the rug, there is no necessary sustainability and sensitivity. If you're concerned about hygiene, there's no problem in washing your legs after school.

(2) yoga clothes. No special clothing requirements. It's just that she doesn't screw up traffic. And second, the teacher must see if you're doing the exercise correctly.

(3) It starts with a small one. Many people are concerned that in yoga classes they will be forced to do some unthinkable positions, someone else expects some kind of circus stunt training. In fact, it's much easier, in yoga classes for starters, usually very simple asans. NO! It's a real yoga practice. Even at the simplest position, try to focus as much on the feelings of your body as possible on the words of the teacher. Don't be surprised if things seem too simple to you (maybe you need a more advanced class, and maybe you don't understand the job). And on the contrary, don't worry if any of the teacher's guidance shows you too complicated to understand and execute. Believe me, it'll be 2-3... Ten classes and words will become understandable and the body will be more obedient.