Become good at CS:GO?

1 - change your sensitivity to something very low that is still reasonably comfortable to you. I use 3 sensitivity so you don't HAVE to use 1 like everyone says, I reached LEM with mine.

2 - Find a custom map that you can practice aim on with targets. Use this to practice 1 taps and accurately switching targets.

3 - Figure out the spray pattern of AK and either M4A1 or M4A4 and then practice it so that all of your bullets go into the same area. Then practice this on targets as well, preferably moving ones.

4 - Learn the maps. Watch videos on how to smoke and flash different spots. Key spots to hide in, etc.

5 - Climb ezpz