Prince of Persia : Rival Swords for Wii!!?

I'm on the level streets of babylon and I am at the part where you are on boards over water. I have crossed the first pat, but the second part when you have to wall run tot he board ( this I have accomplished) and then jump at the wall and jump again when you hit the wall (a wall bounce). I have wall bounced before, but cannot ge this. I got the game only days ago, but have been stuck here since the frist day of play. Please give detailed instruction on what to do..I cant seem to do it even after I try again and again