Organize your documents into folders and by assigning tags.
Tip: As documents are added to Mendeley, it creates a link to where the document is stored on your computer. Be sure your documents are where you plan to store them before adding them to your library.
If you need help creating a file organization system, take advantage of Mendeley's File Organizer (found under Tools > Options in the PC version or Preferences in the Mac version). You can choose to have files automatically sorted into subfolders or renamed using a standard name structure.