When you first create a support ticket without first having signed up, you will be sent an request to activate your support account. 

Activating your account is optional

We request that you do activate the account, as it makes providing you with support more effective - for example, you will be able to add information to a support ticket easily, check ticket status, etc. But even if you don't activate your account, you'll still receive a response to your query via email. 

Just make sure the email address you provided is valid!