I previously used markers to show song structure, but recently I have been doing it differently.
What I do now, is to create an new audio track, and then use the pencil to draw in an event that is the number of bars of the song section. I then rename the event in the status bar to “Verse” “Chorus” , whatever else etc. The visibility is MUCH better, you can colour each event differently, and you can copy/paste for repetitions.
In free improvisation piece, I used the same method to flag transitions, buildups etc. for the early stages of overdubbing whilst the piece was taking shape. For me it’s MUCH better than markers because of the visibility.