Please follow the steps below:
Visit the Lagless website by clicking here.
Scroll down to the bottom of the page and create an account.
Log into the website and click on “My Profile” then redeem your key in the “Insert Key” field.
Download Lagless.
Launch Lagless and Log in.
Click on a game that you would like to optimize.
Click on the server that you would like to play on and then click on “Optimize this game”