The best tennis strategy is similar to those of any sport: win more points and lose fewer points. Use the knowledge you’ve gained by observing your opponent. Use variations of height, spin, and speed to disrupt your opponent’s timing.
If your opponent is tall, land the ball low, forcing him or her to bend. If your opponent appears out-of-shape or slow, force him or her to run from side-to-side or from shallow-to-deep and back again. If for example, your opponent is uncomfortable at the net, you can hit short, then lob or you can make your opponent volley. Do not take unnecessary risks thus making unnecessary errors and losing a point.
Keep defending with varied shots — whether low slices, slow balls, or even moon balls — discovering what neutralizes your opponent’s swing. Finally, if absolutely necessary, simplify your strokes, just blocking the ball but improving consistency.