There is currently no standard or recommended combination. Personally, I have been using Control-Command-P, but that’s just my personal preference.
I would be interested if people could post what shortcut they use. Let’s see what the hive mind can come up with!
(What I would like to do is add the possibility of something like “double-tap Command” (or other modifier) in the future. You’d have to unallocate it from Siri, of course Something really easy to reach for.)
I really like to use what I call one of my ‘claw’ keystrokes.
control-option-command is three fingers in a row, so it’s easy to grab with your left hand, and unlikely to be triggered when you’re typing a keystroke with one or two modifiers.
In my case I use control-option-command-F12 (I use my F keys as plain F keys, not for their pre-programmed functions.)