For classes, there’s no need to dress up. You also don’t need to wear jazz pants, tights, leotards, spandex, or any other type of formal “dance” attire. You can wear “normal” clothing, but make sure it’s something comfortable that allows you to move.
Girls, pants or skirts, dresses are fine whatever is more comfortable for you.
Guys, we recommend full length pants as opposed to shorts. You can wear shorts if you’d like for the comfort but they generally don’t complement the look of the dance very well.
For dances, it’s really your own personal style that matters, although you still want to wear something comfortable. Dress tends to be pretty casual with jeans as most people’s choice, although sometimes people do dress up in nice clothes as well. Women sometimes wear dresses and guys sometimes wear suits when dressing up, and vintage attire is another route people sometimes like to take.
The most important factor for shoes is comfort. Sneakers are often fine for both guys and girls to dance in, although if the soles are too sticky they may be difficult to spin in (one solution to this is to actually place strips of duct tape on the soles of your shoes for dancing).
Ladies make sure you wear shoes with backs and that aren’t going to fall off while you are dancing in them.
Then dance shoes that people wear usually have suede or heard leather sole. Often times you can just go to a cobbler and have them resole the bottom of sneakers or dress shoes.
A store we recommend checking out is World Tone Dance in Los Angeles. They have a huge selection in store that is even bigger than what they show online.