One of the worst things you can do is play a lot of chess.
Think about it, you need to play higher rated enemies since they know how to play better than you. Each game gives you a rating and your rating changes for the win or loss.
Your rating goes up down according to the number of wins or losses, so your job is to win more games on average than you lose. Since each game takes at least 30 minutes or an hour its important that you WIN this game.
If you play a lot of games you make reactive moves without much thought, so you make mistakes and lose material and options thus your rating suffers. This means you must play more chess to 'recover' your lost rating.
Focus on not making errors and losing position or material by reviewing your games afterwards and managing your time so you keep time available to make critical decisions; if your enemy makes a "surprise" unexpected move spend a bit more time to decide if ti radically alters the game position.
Your rating will improve more by studing /reading chess and reviewing your past games rather than just playing more chess; this is proven by the players who spend years playing chess yet never reach master or expert level, or so i have read while i study chess :)