For small amounts, I have a 3 gallon pot with about 6 inches of water in it. I turn the burner to medium heat and throw all the scrape comb in, wires, pollen, dead brood, ETC. once it is melted I pour it through a paint strainer bag into a 5 gallon bucket and let it set overnight. Then I collect the hardened patty and store it.
When I have 10 lb. or so, I put all the patties into the pot with about 1/3 pot of water. When it is melted, I pour it through another strainer and leave overnight.
From there, you can take the semi-clean wax and melt and strain it to the point you want it.
NEVER HEAT WAX ALONE. ALWAYS USE A DOUBLE BOILER OR AT LEAST HAVE WATER IN THE POT.
I do boil mine many times as iddee stated. But it also seems to lose a good amount of it's natural bee smell in doing so. I'm trying to use the solar melter as much as possible. Seems like it works well and retains its smell much better.