If you are competeing as amateurs, as opposed to pro-am, be sure to check the rules for dress. All levels have strict dress codes. Here is what most people wear for practice in my studio. Men: dress pants or dance pants, proper shoes, t-shirts, polo shirts or dress shirts. Women wear skirts or dresses that allow for plenty of movement. Longer length for smooth/standard and shorter for latin. The proper shoe or women's practice shoes. No one practices in jeans, shorts or capri pants.