To get ready, you'll need a form that calls a custom JavaScript function. You can use the Graduation Details client-side customization from the first recipe in this chapter as an example. Ensure the Graduation Details entity is accessible from the Sales module.

You can do so by ticking the Sales checkbox in the entity configuration general tab. You will also need the Edge browser (available by default on Windows 10 and above). If you prefer Internet Explorer, the two browsers have very similar debugging interfaces.