Timeline
Under the File menu, Share submenu, select “Publish to the Web.”
Don’t set your Timeline Google Sheet to “anyone with the link can edit.” It isn’t necessary, and could lead to someone changing your timeline without your consent.
In the next window, click the green “Publish” button. When asked,
“Are you sure…?” click OK. Ignore the URL that appears in the center of the window. Just close the window using the X in the top right corner.
After you close the window, copy the URL in your browser’s address bar. You’ll use this in the next step.
If you get an error message referencing an “Invalid Google URL,” please review the above instructions. You must use the Google Sheets URL from your browser’s address bar, not the one from the “publish to the web” popup.