if you don't want your legs to be knocking the crossbar down, make sure you are getting a fast swing up and try to get inverted best you can. also make sure that you have a good approach and a good plant and that will help your vault too.
that's a bummer that your coach isn't helping you out too much, but there are a lot of posts here that you can read to learn more about technique. i know you're just starting out, but don't get discouraged. these things can take some time. good luck at your meet tomorrow!
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