Tennis is so much fun with two things - 1 top spin serve 2 athletic footwork After toiling for years without them, I wish I knew better when I started out with tennis. For the benefit of others still in early development, my top two things - Learn to hit proper top spin serve- it let's to you swing as fast as you can and still keep the ball in the box, reach any corner because of high net clearance. Second, build and work on footwork patterns and you will be amazed how small the tennis court becomes and how fast you can get to the ball. Quick caution on top spin serve - make sure you really nail down the technique before putting in hours of practice. It's counter productive to practice without learning the proper top spin serve motion. I can say it from my experience- don't rush and waste time and energy. It's not hard if you learn the proper way first.