One spatula and a perio probe will do the trick of inverting the rubber dam.
Deep margins are often challenging to expose solely through the use of floss ligatures for inverting the rubber dam sheet.
Anticipating this issue, I skip the time-consuming step of attempting to place the floss ligature and instead directly start placing clamps.
By doing that, the sheet is nicely pushed over the margins of the facial and palatal, but it rarely inverts in proximal areas.
It takes a few extra seconds of work to manipulate the sheet using two instruments: a spatula and a perio probe, preferably a ball-ended probe, to achieve a better grip on the sheet and force it over the margins into the sulcus for inversion.
I hope you enjoy this video featuring fragments from a few challenging cases isolating anterior teeth.
Wishing you all a Happy New Year! ...