I basically panic, then retrace my steps.
I look everywhere that I have been for the last day until I find it. I won’t stress out until I know I can’t find it.
I ask my friends to check, call places I’ve been, and see if anyone has noticed it.
I’ve got a tracker in it, so it’s easy enough to find.
I’m always misplacing it, so I check the usual spots that I leave it.