I smoke hookah all the time... many factors need to be taken in consideration...
If you use foil... keep the shiny side up... also the size of the wholes matter. Too big= burns too quickly and might taste coal... Too small= will be hard to inhale from the hose... Also make sure the coal is fully lit when you first put it on the head and let it sit for a good 10 seconds before inhaling.
Best shisha I have tried is social smoke... I love pina colada and monster energy drink (mobster) flavor... it is about $13 a can but you get a pretty good amount.
Also, I always use ice and water... it creates more smoke and a more bold flavor IMO.
The way that is seems to take the best effect is when I inhale slowly but steadily for a good bit and exhale really slowly or blowing rings slowly... It is when I feel the effects of it slowly... Also doing it in a small place...