These instructions increase your time to hit unsend from 5 to 30 seconds.

1. When you are logged into your Gmail, click Settings. On the computer, the icon looks like a wheel or gear and appears in the top right.
2. Click See all settings.
3. Under the General tab, look for Undo Send. (At the time of typing these directions, it was fourth on the list.) Use the drop down menu to change the time from 5 to 30 seconds.
4. Scroll all the way to the bottom of the page and click Save Changes.