Hitchhiking is Jamaica just doesn't seem possible. When I was there, almot every person I came in contact with, would ask if I wanted buy ganja or some crafts or things like that. Drivers there travel at high speeds down narrow two-lane roads. It's kinda scary at first, but numerous drivers would swerve to the side of the road when I was walking and ask if I needed at ride. They all expected pay, so hitchhiking didn't happen. Because Jamaica is so poor, many locals support themselves as taxi drivers. Be careful if you do have any luck hitchhiking, especially in Kingston. I heard stories while I was there about people posing as taxi drivers that would pick you up, rob you, and leave you stranded. I found a local scooter vendor and rented a moped, filled up on $2, and drove to another city without having to fill up again. Getting a moped seems to be your best bet in Jamaica.