Demonstration
Step-by-step guide
1
Aim crosshair
Place your crosshair here

2
Throw
Press the keys to throw the grenade
W
A
S
D
Shift
Ctrl
Space
Left clickRight click
Don't hold Shift — run normally
Hint
Take CT spawn position 1 from the preview, aim at the marked point, run forward and jump-throw with left click.
Practice from exact position
Paste in CS2 developer console to teleport to the throw spot