Always start with the melody. Strive to play this one in time, and with minimal mistakes 3-5 times in a row. That's right don't just strive to barely make it through once. Try to play the same arrangement multiple times in a row without stopping. That's how you know you really have something down. Make sure to practice at a speed that is easy for you. Slow and steady is always better than fast and sloppy.
Try out some licks! There's enough to create completely new arrangements.