Scroll down to the Licenses card on the right.
Hover over the license you want to edit. Click on the Edit (pen) button to the right and a form will slide out from the right.
When you are done editing, don't forget to Save!
To cancel any changes you've made, simply click the left arrow in the top bar. You will be prompted "You have unsaved changes. Are you sure you want to leave without saving?" Just click 'OK' and your changes will not save.