We don't offer shopping cart function for licensing, we only allow you to show what licenses you offer and the price for those licenses.

So please sign up for PayPal if you haven't already done this at https://www.paypal.com.

On the PayPal web site (not on SoundClick) you can click the "Products and Services" tab.

PayPal > Products and Services > Get paid > Sell online > Accept payments from anyone > Sell on my own website > Find out more > Sell single items

There they offer several ways to copy code that puts the PayPal button on your page. You can paste that code from PayPal onto anywhere within your SoundClick interview answer fields.