To create one, tap the + button at the top right on iPhone, iPad, and Android. On Mac and Windows, click the + beside PLAYLISTS in the library, or choose File > New playlist.
 
To rename, duplicate, or delete a playlist, tap the three dots beside its name, or right-click it on Mac and Windows. If the three dots are missing you are in Sort mode: tap the X at the top left to leave it.
 
Duplicating copies each song's settings, which makes it the safe way to try a different running order. Deleting offers Delete Playlist Only, which leaves every song in your library, or Move All Songs to Trash, which does not. A deleted playlist cannot be recovered, although its songs can.
 
For more, see Organize your songs into playlists on the iReal Pro website.