- Create or open any Google Doc.
- Click on the "Add-ons" menu and then "Get add-ons..."
- You'll see the add-ons collection. To cut through the list quickly, search for "clipart" on the upper-right corner.
- Click on the "+ Free" button.
- Click the "Accept" button.
Congratulations. Your new clip art system is now installed and ready to use -- in this document and any others.
To use it, just click on "Add-ons", then "Openclipart" and "Search Clipart". (Its easier than it sounds.)
That will bring up a sidebar where you can search for images and just double-click on them to insert them into your document.