Holding large hits:

[YoungShisha]

this is what works for me:
take a pretty large hit, release your finger off the carb when your lungs are 90% full, and then hold the smoke in, and take quick breaths in, like one or two will do, and then release after 5-7 seconds. I think the two quick breaths help.
~stay high

[Captain Hanks]

wow, i thought we allready went over this, ha, of course it doesn't get you higher, unless you like holding your breath to get high! ha