Don't seem to be improving

After 15 years not playing chess, I joined chess.com to play correspondence (online) chess and have now passed 200 games.

I seem to have settled on a rating of about 1400. I tend to find anyone under 1400 I often beat quite easily, anyone over 1500 I struggle to find any ways to attack.

I don't seem to be improving or learning anything new, when I watch people talking about chess and try to apply these things I just get stuck or they don't work.

What one or two key things would people suggest I look at, to get to the next level?

to improve -- playing on-line is great as you get to critically evaluate the position and devise plans.

However you should not limit who you play to the lower Ratings.   When I went to challenge you, it said you only accept challenges from those under 1600.    you have to make up your mind if you really want to improve or not.

I hadn't realised I had that setting, thanks! I fairly commonly play people in the 1600-1800 range in tournaments but don't enjoy those games, I just can't seem to find a way to get into the game.

I challenged you btw and modified my settings up to 1800.

that its not just about Playing- however slowly& carefully- to make further progress in chess.  You ought to have a chess improvement program- training, if you will to make further progress.

What to exactly do is a matter of some debate.  Online is less about quick pattern recognition- but planning runs supreme!  I would give lots of efforts at reading through carefully annotated master games....

for opportunities to play higher rated players- join a group and play in team matches.

Thanks. I can certainly see training would be effective but I play for fun and a rigorous training regime mightn't be enjoyable, so I suppose I'm looking for some basic things. When I try to follow analysis of master games, I feel they're playing a whole different game to me and it somehow doesn't seem relevant!

well, I understand that thought, mb.

but still... its very likely NOT studying is holding you back.  the question is ,can you do a LITTLE without neccesary finding it grueling.   perhaps just do a few tactic puzzles.   go over an endgame or two.  do a mentor course.  youtube is  awash with videos, look up a favorite opening and try to pick up some hints.

anything is better than nothing. 

you get addicted to the training IMHO, when , you win a chess games exactly BECAUSE something you have studied- stuck with you.

----

but I understand just wanting to play and enjoy it.  for me, though, at this time in my life I've resolved to be as good as I can Possibly be.... that is part of what drives my training program.

keep in mind, If your younger you have a great opportunity- it will be far easier to get strong at the game at a younger age....

Continue with the tactics puzzles and chess mentor, also, as others have suggested, play higher rated players this will help your game too. 

  I think it went two weeks without a game once.   I wanted to WIN the next time I played (and I was in a losing streak).

I'm not sure I recommend it-- but it worked.

I find Training More or less fun.  I agree with that tactics puzzles can be the funnest- and great training exercise.

but sometimes you need more than just that.  You've got to eat your veggies... Endgames and Annotated games are very important to evolve as a chess player (espacially in longer time controls).   You've got to see beyond a few tactical motifs to be a strong chess player.

The games of the ancients (Greco, Sarratt, Staunton, Morphy, Anderssen) are entertaining and for most players, instructive. Play through these with a critical eye (and ideally with a friend) and you will improve.

I've only been playing online for a short time and what I've found really useful is the 'game analyser tool' It takes you through every move: your good bits, mistakes, blunders etc.  It gives you a really good insight into what you are doing wrong.  You can then focus on how to improve in those weak areas.

Strongly aggre with shadow... the analyser IS helpful, but really only after we have tried very hard to understand the weakness of our own play FIRST.

its SO easy to see the blunder AFTER you peeked at the solution!

this very much is true for tactics puzzles as well, Make Big efforts to SOLVE them (even if it takes you some time) and the solutions become- Insightful and brilliant.

make a weak, nearly thoughtless stab at the problem- and if you look at the solution- your like "Of course"... --- you've learned nothing. 

I must have played 40,000+ blitz and bullet games over the last 20 years and have been completely flatlined in terms of my rating. I figured, "that's fine, I guess this is just as good as I'm going to get." For several years I read chess books, joined a club, and even had a GM personal coach for a short while. Nothing. Now, all of a sudden at age 45 my rating has jumped several hundred points over the last year. At first I thought it must be just a statistical aberration, but it has been steady and continuous. I've been wracking my brain trying to figure out why?? Is it just some newfound confidence?? That might explain a short term bump but not a steady and consistent improvement.
So why?
Here's my theory. I started playing daily chess! Really spending time thinking about moves. Sometimes 3 hours or more per move! I will also watch YouTube videos about the openings in playing as the games progress. The other new practice I've added is watching live streaming of GM chess tournaments and listening to the commentary. The combination of these three things coincides almost exactly with the start of this improvement. I've begun to believe the sky is the limit for my game and that is a great feeling after being stuck for so many years.