Step 1

- Click the 'Help' tab at the top-left of the screen, and click 'Steam Support' in the drop down menu

Step 2

- In the search bar, type 'Counter-Strike: Global Offensive'

Step 3

- Under 'Products', click Counter-Strike: Global Offensive

Step 4

- Click 'I want to permanently remove this game from my account'

Step 5

- Press 'Ok, remove the listed games from my account permanently'

Step 6

- Never come back