from my experiences with doing this i did use tinfoil on it.. i just filled up the bowl, and why do you need to know how much that is?? andn then for lighting it, just put a light to a side of the bowl so that the lighter just creeps and saves "greens"... and just burn til its lit.. youll know..
"If you my homie you my homie til we go, one of the few I would take a bullet fo, lets toast til we die, roll up the weed and blow the smoke in the sky"
"But I say when im deceased, put an ounce in my casket and let me smoke one in peace"
"I ain't touchin that dirt, i aint smokin that shit that make your whole head hurt"