Save playing for when you get good.
Advancing from rating 900

Looking at common opening traps, working tactics, and just learning about how to understand the general positional strengths of the pieces board helped me get past 900 more than anything. The players through random moves at you and you need to be able to analyze things and see past their bluffs. If you just treat it as a normal game and continue playing an opening your used to without watching the strengths the "bad" moves are giving them they will be able to beat you once they shake the position enough to find tactics. But a lot of the moves are not that great and they make serious weaknesses, if you learn how to identify them better 900 should be no problem for you

Tactics, tactics, tactics. And then more tactics. That, general opening knowledge and basic endgame knowledge will take you to an intermediate level of play. And if you really apply yourself, you can get there relatively quickly.

Thanks jhubchess, MechHand and ilikewindmills! Sounds like you all would suggest more work on tactics! Your answers are much appreciated!
The easiest and most fun way to improve is to find a human or humans to teach you. If you don't have family or friends, then the best place is a chess club. My buddy and I started when we were 13, we were in a club with mostly all adults ranging up to mid-expert. Thing is, everyone is at different levels, and chess players know that kids can get incredibly strong incredibly quickly, so there was nothing but welcome. After you get your but kicked, you ask if they will go over the game with you. Note that this works much better if your club does one long game on a weekday evening, rather than just 3-4 games on a Saturday, where there is less time to go over games. I never made expert myself, but my buddy is an upper level IM (borderline GM strength) that was making a living at chess, last I checked in.

40% tactics 50% play (you'll get bored if not) 10% opening (starting with a good position is always usefull.

Get out your chessboard and look over classic games that were played 1850-1950.
It's the best thing you can do.

Hi Urk
Interesting with some dissidence from what seems like a tactics consensus. What are the reasons behind your view? And how do I find the games you refer to? Any book suggestions?

The games from 1850-1950 feature wild tactics most of the time, quick development, open positions, and someone getting mated, he is just offering another way of studying the same thing, tactics.

Get a collection on Morphy, Janowsky, the young Steinitz, or other attacking players and play trought their games, however I would still recommend doing some tactical puzzles.

I improved from 900 to 1100/1200 by doing one thing. You need to make sure you are not blatantly dropping pieces. Make sure when you move a piece somewhere that it isn't capturable immediately.

If you play for fun but want to improve you will have to give up blitz and focus on at least 15/10 games where you can think and analyze them afterwards to see flaws in your thinking process.
Slow chess games are also fun, you just have to find the beauty in sitting 3-4 hours in front of a chessboard thinking about your next move.
For that I would recommend OTB tho.

When I first played, I was stuck at the 900s for the longest time too. And I just kept playing, and the more I played, the more I recognized moves that didn't work or moves that did and you'll get into this pattern recognition thing where you'll kind of move intuitively because you've seen this situation before. I also experimented a lot and find which openings work better, etc. Tactics training didn't work for me, actually playing real-time taught me more tactics than most training. I would occasionally bump into a player and be like "woah how did they do that" and I learned from their tactic and style. I would suggest to keep playing, and if you feel disheartened by losses, you can choose easier opponents but the more you play, the more you'll improve. And the most important is to enjoy the game, you'll soon know what works for you and what doesn't.
I have no chess ambitions, but I like the game for fun, and of course I would like to improve. But with limited time for Chess, what is the best way to improve gradually? Where should I put my time and effort?
1. Tactics?
2. Lessons?
3. Gameplay?
4. Study my own blunders?
5. Study other peoples games? -if so what level?
6. Reading? -if so what?
Now I think I spend my time like this: 90% gameplay, 5% lessons, 5% Tactics?