For less busy intersections, people just treated them as 4 way stops.
For busier intersections, say a 3 lane road with a 2 lane road crossing it, there was sometimes a police officer to direct traffic. But sometimes not, and that’s when it got interesting. What would often happen is that the different traffic directions would try to take turns. One direction would get momentum going until someone brave enough in the other direction would poke their car out. Eventually the one direction would stop and the other direction would start going.
But sometimes even that could not work. And this is when the volunteer traffic director would appear. Someone driving with a passenger would have their passenger get out and start directing traffic till their car got through and maybe for a couple more minutes. Then that person would go get back in their car and suddenly another volunteer would hop out of another car. Serial volunteer traffic directing is one of my enduring memories of Miami from that time.