1. Go to 'My eBay' and click on the 'Account' tab
2. In the 'Payment Method for Seller Fees' section, click the "Change automatic payment method" link
3. Select the option for 'PayPal' and click 'Continue to PayPal'
4. Select the method you wish to pay through PayPal then click 'Continue'. Note: your options will not be the same as the screenshot provided
5. Click 'Agree & Continue' when prompted with the next page
6. You're all set up with an Automatic Payment Method through PayPal!
Also, here is a general article on eBay explaining more about automatic payments and how to set them up: https://pages.ebay.com/help/sell/automatic-payments.html