If you find that a report is one you intend to use again in the future, you may want to mark it as a "favorite." To do this, simply click on the star next to the name of the report so that it turns yellow. When the star is yellow, that means the report is favorited. You will now find that report under the "Favorite Reports" section.
Here, the report is not a favorite.
Here, it is a favorite because the star is yellow (after clicking on it).
And now it shows up in the My Favorite Reports section: