How do I get better at CS:GO?

This is my opinion, I personally go on to aim maps where I can shoot bots that either have guns, or are running and you can choose how many bots are on teh field and their weapons they are equipped with. I suggest that because then you can learn how to prefire or preaim on heads and recoil patterns. Another thing is making sure your crosshair is placed where you think a head could be, this takes game sense and common sense, but try to put your crosshair where if someone was there you could shoot and get the headshot instantly.