How to reach 1800 rating?

There are many advices about how to improve your chess skills. I assume they all work if you are at an appropriate level.

However, my best rating was slightly above 1600, now it dropped even below that. Maybe it dropped because I tried to improve in wrong ways.

Maybe trying many different approaches does not help and only decreases your skills.

One of my biggest mistakes is probably that I play too much.

So, how should someone of my level approach chess learning? What should I try to do to reach 1800 level?

Could you explain not just what to do but how to do it and why?

I'm sure others will give better advice. I just wanted to share something that helped me.

While I was going from (an OTB rating) 1600 to 1800 I found myself in a club where I was the lowest (or 2nd lowest) rated person. Almost all my games were against 1800 and 1900 players which was very useful to me.

Secondly I developed a thinking system at the time to help. For a candidate move to be satisfactory it had to satisfy about 4 conditions:

1: If my opponent directly attacks the moved piece (or something it was defending) do I still like my move?

2: If my opponent directly defends against my plan or tactic, do I still like my move?

3: If my opponent tries a counter (either a tactic or strategy) on a different part of the board, do I still like my move?

4: If my opponent completely ignores my move and just makes a simple development type of move somewhere else, dd I still like my move?

I reviewed every game with a database and reviewed many GM games that used the same openings. I also solved tactic puzzles. I read Pawn Structure Chess by Soltis.

For you a different book may be better. I recommend picking something you haven't read yet from the following general categories: endgame, strategy, tactic puzzle book, annotated game collection. When you read the book take notes. Never rush though analysis. Every couple of moves pause and think what you would play before continuing. If you're too tired to do this put the book away and try again tomorrow. It's definitely possible to read or watch things and learn nothing.

Thank you. That seems like a very good advice.

But what does it mean to review grandmaster games? I heard this many times and I try to go through their games but I feel like the way they play is too high level to be useful in my games.

Soltis's pawn structure chess helped me a lot with that. He talks about strategy revolving around where the pawn breaks are for each player, and what area of the board a player will try to play on (queenside, center, or kingside). I just used a very primitive sort of classification like that. I looked for:

1: what area of the board does each player want to play on (kingside, center or queenside) and
2: how will they do it (with pieces or pawns). 

I'd play over the games fairly quickly, maybe even as little as a few minutes for one game. After a few games you start to notice some general patterns like the area of the board, and the main way they do it (with pawns or pieces).

Then in one of my own games I would try to copy the general strategy and I might get it totally wrong lol :) Because it's a different move order or a different variation. Then I look at some more games with the variation from my game and I see how that different variation changed things, and then the moves start to make more sense.

I guess I should have said I use chessbase.