Great! you've decided to try out a class but you're still a little nervous. Let's talk about what you can expect and what you should know before you go. Now as always this is just a general outline and not all classes or instructors are the same.
First let's take a look at some things to do before you even get to your class...
WEAR WHATEVER YOU WANT. Wear something that is comfortable to move in. More important than how you look is how you feel and this is true for all aspects of yoga - outfit included. Try wearing something that is non-restricting but that you won't be tempted to fuss with the whole class. My personal preference is leggings or long spandex shorts and a top that is not fitted but will stay put when I'm down dogging. Think athletic style t-shirts that are breathable and possibly moister wicking (your girl runs real warm). Real talk here, for the busty on top yogi make sure you have a supportive bra and in my experience a wider strap can be helpful. For my guys just be aware of wide legged shorts and preventing spillage.
All of that said there is no right or wrong outfit and it's all about what you are comfortable with. Ive seen all kinds of outfits for yoga and they are all great in there own way.
-Props and equipment-
I highly suggest bringing your own mat and the good news is you can get a mat for cheap. If Lots of studios have mats you can borrow so that is also an option. As you become more seasoned in your practice you will find things that you like and dislike about different mats but start with something basic.
Blocks and straps are a fantastic add on to anyones practice and can be very affordable. I highly recommend including props in your equipment just incase your studio doesn't provide them as this will just help make your class much more enjoyable. A bolster or cushion can also be a fantastic add on for classes like Yin.
Bring a water bottle. Staying hydrated is so important.
Use the washroom before class. Sometimes yoga can get the removal system going and it's not fun when you have to climb over other students to excuse yourself so always make a pit stop before class starts.
Bring a towel. This one is a big one for me but not necessarily everyone. I run warm when I do yoga and I get a little drippy which then leads to a little slippy so I find it nice to have a towel on hand.
Check and see if your studio has any rules about arrival time and check in process.
OK, get to class already.
Try to arrive a few minutes ahead of time as the instructor will likely be there and will have some time for introductions.
Introduce yourself to the instructor and let them know any questions or concerns you have.
Set up your mat and equipment before the class starts, this way you won't be looking around for things in a dimly lit space.
Be open to trying things you may not have thought about trying. New poses, mantra, being adjusted.
Be yourself and if you find you are very uncomfortable evaluate that and see if the class is a good fit for you.
Most importantly have fun and enjoy!