You do not need to sign in to Paypal to use a Debit or Credit Card.
Clicking on the Buy Now button takes you to a PayPal payment processing page. On that page, fill in the description as “Join” or “Renewal.” Fill in the amount (just the number; don’t use a dollar sign), and Click Continue. You will be given the option to Pay with PayPal OR Pay with a Debit or Credit Card. Select the option you prefer.
If you use a Credit or Debit card, skip the email and password fields and go directly to the next page to enter your card details.