You can create bookmarks to commonly used folders which will then appear at the top of the FX "Home Screen".
To create a bookmark, first visit the folder which contains the folder you want to bookmark. For example, if you want to bookmark the "Download" folder on your SD card, open the "Media Card" (or "Main Storage") catalog on the home screen. Then tap-and-hold on the "Download" folder and select the "Add Bookmark" option in the pop-up menu. If you then navigate back to the home screen, you will see the bookmark at the top of the screen.
You can rename, rearrange, remove, and edit bookmarks. To do so, tap-and-hold on the bookmark on the FX home screen. By using the "Edit" option, the displayed name and icon of bookmarks can be changed.
When opened from the home screen, a bookmarked folder will behave as though it is its own file catalog. That is, opening a bookmark and then pressing the "Back" button will take you back to the home screen, not the bookmark's parent folder.
Many Android applications aren't particularly courteous about where they store their preference files and data, often creating one or more folders in the root of your phone/device's user storage areas. It thus often makes much sense to create a few important personal folders, e.g. "Documents", "Pictures", "Music", and "Videos" in the root storage directory and then using bookmarks to access them. This avoids having to deal with the clutter of these miscellaneous application-specific folders.