This could be the shortest tip I've ever written, since it's all in the rather long title, but I'll elaborate. One of the things I always advise players is that if they don't have something that threatens an opponent, you can't beat them. It's a simple as that. Therefore, at whatever level you are currently at, you have strengths that threaten other players at that level. If you want to reach a higher level, you have to turn those strengths into overwhelming strengths, ones that would even threaten those at higher levels - thereby putting you in a position to actually beat those "higher-level" players.
So look at your game and decide what are your current and future overwhelming strengths. This not only includes the strengths themselves, but also - and this is key - the techniques that set up or follow up those strengths. Having a great forehand could be an overwhelming strength, but less so if your serves and receives don't set it up, or if you don't have the footwork to get into position to use it. Having great serves could be an overwhelming strength, but less so if you can't competently attack the weak returns. Even a push can be an overwhelming strength - but only if you are also strong at blocking or counter-attacking against the weaker loops they force. And so on.
Here's the key point. Once you have a foundation to your game, you really need to start developing overwhelming strengths. You can't do that by just practicing those shots a little each session. Instead, you need to spend a good portion of your practice time developing the things you do that can threaten better players, even the best players - and then, maybe, just maybe, you'll develop techniques that threatens everyone, and ride those strengths to the top!