After you have made payment and got confirmation it was successful, you should be getting an e-mail to your registered e-mail with a link to follow to activate your account and set up password.
Usually e-mail arrives instantly, but there can sometimes be a delay for up to 10 minutes. We also ask to check spam folder as sometimes activation e-mail can land there.
If you haven't got an activation e-mail within 10 minutes after payment, please, contact our support. It might be the case that you misspelt your registered e-mail or trial got registered for a different e-mail.