At ranged weapon distance, display your weapon hand raised to shoulder level or higher, fully open. Move it from side to side for additional visibility if range merits.

At melee distance, extend your open weapon hand outwards and await your counterpart to do the same. Clasp hands for a final confirmation that neither party is armed, which serves as a proxy for an absence of hostile intent.

Take it as an opportunity to size up the strength and resolve of your counterpart by giving his hand a firm squeeze and a slight vertical shake.

If someone comes at you with a closed fist, assume hostile intent from an armed opponent. Proactively eviscerate him and, if it's not a bountiful season, eat his corpse.

we live in a society

whether it’s fist bump v. handshake or picking a side to walk past someone on the sidewalk 

you gotta telegraph your next move like a dark souls boss