The way I normally do it is to place items into the queue, view the queue by pressing the symbol top right on the room screen,  move them around if needed (by selecting edit, then holding the right hand symbol) and then select save.

Ralpfocus, thanks but after I do save the queue, I can’t find it in the Playlist, or anywhere else. Where’s it  hiding?

Choose My Sonos from the bottom of the screen and scroll through to playlists, then press on the word playlists.

HTH