Dude , i was calibrated at 2600 mmr but i managed to climb it to 3.1kby spamming support sand king in every game. Its not 100% winrate but its someway around 70%-80% winrate around it. The idea is the first item u buy is boots + ( ward or courier )..then u go to the lane with the lacking help in it be it trilane or off. then after u gank(once u are level 3 with 2 points in sandstorm) whether its successful or not u go to the jungle and stack camps.Remember to not farm it straightaway because u may lose some stack in other camp while u are farming. after u got 3/4 stacks in 2 camps farm it and rush blink. After u got the blink u just make the play . Remember to aim the low hp target once u get ur ulti .

here i provide u my dotabuff link for reference My dotabuff

my advice is , use the best hero you good at...here's mine..trying hard to get 4k for this week..

http://www.dotabuff.com/players/101888997

Don't chase your rating down the rabbit hold. Re-examine your play and improve from there.

I've been playing a lot more with lower rated players, and many losses have taught me what parts of my game I need to improve on so that I can carry them to victory. My main account may have tanked closed to -400 party rating points over the last few months, but as a result my solo rating on my smurf has gone up to almost 5.2k now. The best piece of advice I can give you is this - add players from different skill brackets. Learn from the good ones, practice with the not so good ones. Take what you observe from a better player and apply that to carry the lesser ones.