If you wish to support your favorite creators through Buy Me A Coffee, you do not even have to sign up, let alone set up your page.
Simply select the number of coffees you wish to buy and click 'Support'. Name and Message boxes are optional. You can pay using PayPal or any major credit/debit card and they might ask for your email or name.
Here is a screencast of how you can do it.
For monthly subscription, however, you will be required to sign up on Buy Me A Coffee. This allows you to later change or cancel your subscription.