To become better at something you need to challenge yourself and move outside your comfort zone (besides practice, practice, practice of course). You need to dare trying different shots and losing training matches you wouldn’t lose or lose as badly with your standard game plan. Let’s say you want to broaden your tennis game and introduce a new shot – let’s say the drop shot, then you need to make sure that you dare to play it in a match situation to gain confidence.
If you’re a sore loser or hate losing also against your practice partner this can be tough, but at least try to be more experimental with your shot selection for a set and if it doesn’t work and you still want to win the match, switch back to your standard game plan. But you need to “sacrifice” at least a set without losing your head to make sure you get proper practice with your new shot. This could go for the drop-shot like I mentioned or a new service motion or, what I’m working on right now, your serve-and-volley game.
I’m not a tall guy with a big serve and a wide wing-span so the serve-and-volley game comes far from natural to me. Instead I’m more of an aggressive baseliner where I’m often reluctant to move in and finish my shot and instead rely too much on my firepower which, pure geometry tells me, lessens my margins by quite a bit.
So, for me it’s not really serve-and-volley, but my volley game. I simply want to add that tactic to my strategy and be able to kill points faster and not get stuck in extended baseline rallies with some of my very defensively skilled opponents.
You could tell me to play more doubles and that’s a good idea to improve your general reaction time and volley skills, but I also want to improve my lateral movement and be able to get to the net quickly and at the right time.
And how do I try to improve my singles volley game? It’s easy, besides practice, I decide to dare to lose points, games, sets, matches (in training) here and there to be able to win them easier in the long run. It’s not easy and sometimes painful to play points in a (for you) less effective way, but it’s the only way to really improve your game.
So my tip to you is not to only play tennis to win matches, but to keep your mind on always improving your skills and becoming a better player. That way your enjoyment out of the game will grow and your results (in the long run) will follow.