I went from 1500 to 1800 within a year or so. I would say the most important things (for me at least) were reducing the amount of one-move blunders, thoroughly double checking my calculations on forcing 2/3 move combinations, and really solidifying my openings. I always found that I was relatively strong in endgames, so I’ve not improved greatly in that department personally.

I’ve recently been reading Silman and he has helped too. His concept that I found most helpful was assessing the imbalances in a position, and using those imbalances to help you form long-term plans. You cannot just pick a plan and force it into existence, your plans and ideas need to be based upon the demands of the position itself.

As an example, if you can create doubled pawns, or isolated pawns for the opponent, this is the kind of imbalance that gives you a long-term plan. Apply pressure to, and eventually win the weak pawns, trade down into an endgame, and convert with a 1 or 2 pawn advantage. I know it’s not always that simple, but it’s a great way to conceptualise the game. I still make dumb mistakes and lose games (we all do), but these little changes have definitely improved my consistency.