TRAIN LIKE AN OLYMPIC TENNIS PLAYER: GO FOR THE GOLD...
Schedule a private lesson once per week to focus on learning how to compete and how to win. You can google nearby tennis clubs and see if their program offers lessons.
Take as many opportunities as you can to get out and play! Set up some casual matches with friends and family to reinforce the skills and techniques you learned in your lessons. You can also work with a ball machine for some solo playtime.
Register for as many competitive matches as you can, and participate in tournaments and round robins. Really implement all of the skills and techniques you worked so hard to learn. Go out there and win!
OFF THE COURT
When you aren't on the court, focus on developing fast starts and quick turns. Really try to improve your agility with things like ladder drills. Also, focus on improving your cardio with plenty of aerobic exercise; this is important for your stamina, allowing you to player harder and longer.
ON THE COURT
While conditioning on the court, use drills that will improve your fast-acting footwork. Try shuffling from side to side, using the length of the tennis court as a marker. Sprints are always an important part of conditioning, and can be used as a way to track your improvements.
Staying hydrated is one of the most important things, so remember to bring a water bottle to ALL of your conditioning sessions, lessons, matches, and tournaments.
And always remember to have fun!