They have weekly open calls at all of their locations (NY, LA, Miami). Look online to see when they are in your area.
Height requirement for female models is 5’ 8” and above. They aren't interested in anyone much over 6 feet.
Dress: little make up and simple/natural dress code. Heels (not too high), jeans, solid color top is better. You don't want to wear ridiculous heels, too much make up, or look like you're going out.
Bring: Portfolio, swimsuit, and some digital snapshots.
You'll arrive, fill out a fairly simple form of general info- name, age, height, measurements, previous work, etc., You'll then wait for the receptionist to look over your portfolio, they'll bring it into the back office for review, and they might simply return it to you and say it's not the look they're going for but thank you for coming by.
If you get past that, an agent will come out, look through your porftolio with you, ask you some questions about your work. Many people lie about their height and age, so they'll often try to verify that too.
If they are still interested, they'll take some snapshots of you, and ask you to take some in your swimsuit as well.
They may have you take some test shoots with a photographer on file with them and see how those go. If all goes well, they will sign you, and start sending you out on auditions and see how you do.