The Standard Reports accessible to you after clicking Reports from your navigation menu on the left in Redtail are divided into several categories with specific reports under each of those categories. The exception to this is the "Favorite Reports" area at the top of the Standard Reports page, which displays the names of those reports that you've marked as favorites in Redtail:
Note: each individual database user will see their own list of Favorite reports, i.e., when you mark a contact as a Favorite, this has no effect on the Favorites list another database user sees.
To add a report to your Favorites category, find the report underneath its appropriate category on this page and click the star next to its name. To remove a report from your Favorites, just click the star again, either from within the Favorites section or from within the specific Category section.