If you are paddling for a right and a surfer on your left is also paddling for it, you must yield to him or her
OR
If you are paddling for a left and a surfer on your right is also paddling for it, you must yield to him or her.
In the example below, Barny is paddling for a left, but a surfer on his right (Fred) already has the wave. Barny must yield to Fred.
Rule #1 to Surfing Etiquette: Don't Drop In!
Fred is closest to the peak and has the right of way. He is obviously standing and riding this wave. Barny should STOP paddling and get out of Fred’s way. If Barny continues to paddle for this wave, catch it, and start surfing in front of Fred, this would be called DROPPING IN. Dropping In is considered to be the cardinal sin of surfing. Dropping in on another surfer and obstructing or interfering with their right of way is dangerous and disrespectful. You just ruined their wave… and that is a pretty lame thing to do. Make sure you look both ways before dropping in every time you paddle for a wave.