how to add visa to ap module for receipt

I send my invoices off to auto entry for entry and need to be able to pay with visa.  I have to have time between so owner can approve these invoices (I  am 100% remote).  I advise when invoices are uploaded for him to see them then he will advise ok to pay.  when I go to my payment screen I do not have option of visa in the payment methods listed and for the life of I cannot remember how to do this (been quite a long time since I had to set this up).  Could someone offer how to do this please. I cannot have it go through ap invoicing and defaulting to paid by visa, needs to be pay later. 

Thanks