How do you correct improper tracking of the patella?

Many options. There are many options to address patellar maltracking. Initial treatment should include a hip, core, and leg strengthening physical therapy program. Supportive bracing may also be helpful for sports and activities. Surgical treatment can involve soft tissue releases, bony realignment procedures, and ligament reconstructions.
Orthotics. Orthotics and shoes can alter the gait and allow the patella to function better.
Physical therapy. Usually physical therapy will be the answer. See a sports medicine trained physician, who can make a diagnosis, and prescribe physical therapy.