The YoYo Account is a one-stop solution to all GameMaker licensing requirements. Once you have made your account, you can use it to recover your licence details as well as for logging in to the GameMaker Marketplace or even purchasing additional GameMaker Licences.
To create an account simply go to https://account.yoyogames.com/login and then fill in the required details:
Once you have filled in these details, click the Register button and you'll be taken to your main dashboard where you can purchase a licence (or further licences) as well as edit your profile, create gifts or set up Marketplace publisher account:
Note that when you go to purchase any GameMaker Studio 2 licence from the YoYo Games website, you will be asked to make a YoYo Account first before you can go to the checkout to pay for the licence.
If you have a GameMaker: Studio 1.4 licence and wish to link it with a YoYo Account, then you should create the account (or log in if you have one already) and go to the section GameMaker > Redeem, and there you can input your GM:S 1.4 licence key to link it to your YoYo Account: