Select your buyer requirements. These include blocking buyers who:
Buyers without a PayPal account
Buyers with Unpaid Item strikes
Buyers in countries to which I don't ship
Buyers with policy violation reports
Buyers with a negative feedback score
Buyers who may bid on several of my items and not pay for them
Click the button to save your buyer requirements.
Then, on the listing form, last yellow bar "Other things you'd like buyers to know", click the add or remove options link and select Buyer requirements.
Remember, the Selling Preferences sets the blocks,
the listing form invokes those blocks.