Aiming in CS GO is one of the essentials in game and will help you to climb the rank ladder.
First of all make sure that you have perfected your sensitivity.
Make sure to download the training map training_aim_csgo2_dark (check link below)
To warm up on csgo aim dark pick the AK and choose intensive fast aiming from options.
Set the color of your target and size to your liking .Try to do at least 200 targets then change your training mode to classic.
Set the size of your target to 12 R or lower , amount of targets to 100 and delay to 0.25
Try to hit as much targets as possible and track your score every time to see how you are improving over time.
Do as many rounds as you wish, then move to community deathmatch servers that have headshots only enable.
This will help everyone who isn’t used to hit at head to get used to it as on this servers nothing else deal damage except headshots
Try to spend at least 15 to 20 minutes here.
If you practice this routine at least three days per week, you will drastically improve your aim
EXTRA TIP : Find a sensitivity that you are confortable with and keep it constant as this is great way to build your muscle memory.