another thing that distinguishes foreigners from locals is their scent. your deodorant, soap, detergent, and diet gives off a different body scent that you won't pick up cause you're always smelling yourself but locals definitely would, especially in tropical countries. another thing too is your skin, even if you're dark skin, tropical people skin is more hardened by the sun and it's clear to see. either way, trying to dress like locals won't do shyt.
Move with common sense, carry yourself with some confidence (most crooks are looking for an easy lick, don't look like one) be aware of your surroundings, don't linger around too much in local places, always keep moving, don't let anyone bring to get weed or anything else. when dealing with women def don't go to their place, and unless it's a hotel or a gated security area don't let them stay over night. fukk and let them bounce.
edit: another thing is to put down the damn cameras. unless going on an excursion in the wild no need to be walking around with one to snap a bunch of bullshyt pics in an urban setting. use your phone and be aware of who you mind be filming.
example here. this bro almost got his food ate being reckless with where he was filming at. he was with a guide so i guess he felt comfortable but guide or no guide use your own senses