1. Click on the link to the Interval Timer folder. (Make sure you are logged into your Google Account).
2. Add the folder to your Drive.
3. Open Google Slides and decide on which slide you want your interval timer to go.
4. Tap "Insert" then choose "Video..."
5. Select Google Drive, then Shared with me.
6. Select your preferred timer (20-20-20) or (10-20-20-20), then click the "Select" button.
7. Adjust the size of the video using the blue dots.