If you paid one-off, you can just let your account expire. You don’t have to do anything.
If you have a subscription, you can stop it by clicking the Stop recurring payments link on your Payment page:
If you need to delete your account permanently, you need to also click on Destroy my account from your Account page. But usually there is no need to do this, since it would destroy account completely and irreversible. Please only do this if you are sure about the consequences.
Also don’t hate me because I’m beautiful 💄