There's a video on how to fix harsh smoke by our own Sambooka! http://uk.youtube.com/watch?v=2zvN1cL1uik
When you prepare ure bowl just sprinkle the shisha. . .dont pack it . .keep your charcoal to the edge of teh bowl, and put the tin foil with the shiny side facing the shisha to relfect heat towards the inside, and make sure you pipe goes hlf an inch into the water if our hookah is small or over one inch if you hookah is the large kind. Try adding a bit of milk in the water to thicken your smoke. IF all thsi doesn't work . .check your hookah fo leaks.