Every level has a secret Surf Spot. Find the Reef Girl. She usually hangs out around The Shoreline of each level. At Hossegor, she is next to the wall in, between some pylons.
Shark Infested Waters under the Islands
Select the wave closest to land and paddle to it. When you hit the land, keep paddling until you start to bounce.You will go under the island in shark infested waters.
When you are in the water hold L2 + R2. When your player surfaces, keep holding the buttons. Your character should go back underwater, except deeper this time, allowing you to stay under longer.
Toggle Hud Display
Press Select, Up, Down, Left, Right, Up, Right, during game play.