Some other cues:
1) An undercover officer sitting in an airport. Seriously, a fishing hat, sunglasses, pastel shirt, Dockers and Hush Puppies loafers, having talked to another officer, he sits down and crosses his legs, showing his ankle holster.
2) An emergency room where a dummy has either shot himself in the genitals and thigh, or buttocks, by shoving his gun into his belt without a holster.
On that second, waistband carry, aka “Mexican Carry”, is just brain dead stooopid.