How to get from 4k to 5k MMR?

I'm ranked at 4k solo and i have to admit that I belong there as my performance is not always stable. My question is how do you get better? I've played 2000+ hours in DOTA 2 and probably 4000+ hours in DotA 1. I've put in the time watched all the replays, my understanding of the game is pretty solid. What is there that I can do more to get better?

Pretty much the same story for me. I got calibrated at 3.8k (have no idea how this happened) but pretty fast got to 4.6k. I haven't played much after that and I mostly played carry/hardlane heroes. But I actually noticed 2 things at that point:

• Even though I'm extremely good at farming and finding my farm in almost any situation, I'm terrible at making decisions in huge team fights. 
• People most often play supports just because they have to because of the team picks. And they suck with them in the end.

So from carry/hardlaner I switched to support/hardlaner. And I REALLY enjoy playing supports. Making right decisions as support sometimes feels better than making a rampage with 6 slotted carry. And with the proper mindset and a LOT of communication in voice chat with the team I got to 5000 in a few weeks.
And most of the time I picked supports that I'm good with (Lich, Crystal Maiden,Treant Protector , Witch Doctor, Dazzle) even if other supports that I'm not so confident with (like Shadow Demon, Disruptor, Io) fitted our lineup much better.

As for support gameplay:

1. Map awareness is key. Placing the RIGHT ward is very important. Is your lineup farm oriented? Or your team will most likely force the fights early? What does the enemy excel at? Your warding must act accordingly. 
2. Smoke. Use it either for ganking or placing some unexpected wards on the enemy territory. Sometimes it can even be used defensively (hiding your low hp from bloodseeker or dodging a projectile f.e.) 
3. Make the calls. Keep an eye on everything that's happening on the field. Call misses for every single lane, inform your team on enemy item progression. This is actually a small thing that a support should always do imo. 
4. Stack! Stacking gives your team so much, but is often overlooked in pub.
5. At the moment I play just a few games a week, But i'm pretty sure I can get another 200-300 points before stopping. And that's where I'll probably have to improve my other supports.

To stabilize your performance one of the biggest thing is to limit your heropool by a lot to start with, play the  heros you know you win most of the time and can always have a great impact. After this do the same with the role you play, just take a priority for example, always offlane. Play AP and counterpick the opponents, meaning you lastpick a good highimpact hero, like picking Nyx Assassin against Tinker or Batrider.

Remember that in order to raise MMR your "fun" level of gaming will suffer, you do the same stuff over and over again until your mind and dreams fill up with it and you perform at the optimal level, play to win not for fun

In the end though it comes down to yourself and what you get out of every game, be always analytic of yourself, your performance, hero pick and attitude towards teammates during a game.

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