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afterward, i would compete in as many tournaments as possible / watch higher level games. playing at a high level doesn't come from ladder usually, to be truly good you need to play people who are at or above your level consistently.
first, i would try and sign up for battling 101 when a new round is posted. i believe they have a schedule on when rounds are posted. this will supply you with a tutor who should be able to teach you the basic instruments of competitive pokemon and make you better.