First, click into your Inventory tab.
Then, click 'Services' on the left hand side of your screen.
Click the service's name you'd like to edit and click the 'Pencil' icon in the top right.
Or click the three dots on the right and click 'Edit'.
Finally, make your adjustments and click 'Save and Close'.
This new description will apply to all projects you add this service to moving forward.