In my experience, it really would be best to show up and be ready to learn. Now most lines won't teach you everything, but on day one they'll show you their approach to things. All you really need to do is look at their packet, learn what your asked to, and be ready! From what I'm told though, World lines is more of the level where your expected to know your stuff, and Open, A's, and the other levels are more along the lines of doing some "teaching" so to speak. All lines will give you a basic walk through, and they'll work with you as long as you present yourself as a person ready to give it your all. Just like banddirector514 said, get some material, learn as much as you can, watch videos, and show up to auditions ready to throw down! Good luck man!
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IPT-Bass Five '09
IPT-Bass Four '10
TAMUK Quads '11