I put up a series of screen photos on flcikr as I think I lost a customer who just gave up because they did not know how to pay with a credit card through paypal, so I hope this helps.
~~~Refer to Step 4-6 for to direct buyers on how to pay with credit card. They do not need to sign up to paypal.
The links are screenshots of what happens with each step.
Step1 Choose product. www.flickr.com/photos/natureautumn/1547844042/
Step3. Confirm Address
Step4. Choose Payment Method as PAYPAL. Can pay with Credit Card Later
Step5. Click Button that says Pay with PAYPAL. Can pay with credit card later.
Step6 : You can choose Credit Card Payment
Step7 : You fill in the credit card info.
Apologies if the ones on flickr were not too clear but I hope this helps:)