Step 1: Log into your PayPal account and navigate to Merchant Services > Buy Now Buttons
Step 2: Fill the required fields with your own product name, currency, price etc. When you're finished, do no click on "Create Button", but instead click on "Step 2: Track inventory, profits & loss (optional)" in order to roll new options.
Step 3: Here you need to uncheck "Save button at PayPal". This will disable saving your button as hosted button. When you're finished, click on "Create Button"
Step 4: Now, in "Website" tab, you see encrypted PayPal button by default, therefore you have to click on "Remove code protection".
Step 5: Now you should see unencrypted code of your PayPal button. Click on select code and you can copy&paste it to your website. Now you have non-hosted and unencrypted PayPal button ready for integration with Post Affiliate Pro.