Click here to sign up then fill out your username, password and email
Under "Have a Voucher?", enter code FACTORY2
Select "Create Free Account"
Separately, you will get an email immediately sent to the email provided in step 1, click the link in the email to confirm
Once you confirm email from step 4, your account dashboard should now display the 20GB limit
If needed, you may claim the voucher code by clicking "My Account" (top right side of page), "Claim Voucher" and then entering the voucher code FACTORY2