There are two ways to smoke DMT from a regular bong. Enhanced leaf / changa, and sandwiching.
Enhanced leaf is some kind of smokable plant material infused with freebase DMT. Changa is some kind of smokable plant material infused with a mixture of freebase DMT and harmine (technically, it's usually an impure alkaloid extract of
P. Harmala or
B. Caapi, ie. a mixture of harmine, harmaline and some other alks).
You can find teks for making these. It's not hard and a lot of people swear by them.
As for the sandwich method, you place a layer of a smokable herb in the bong, you put some freebase DMT crystals on it, and then you cover it with another layer of smokable herb. This way, as you light the herb on top, you're not burning the DMT, and as the DMT crystals melt, it will be soaked up by the lower layer, and will stay there in the path of the heat as you pull, and get vaporized.
I specifically recommend NOT to use cannabis for the plant material in either method. Some people like the combination of cannabis and DMT, but most don't. Blue lotus is good, or lemon balm, or any non-psychotropic herb. You can try weed sometime, but it'll be a hit or miss (and the miss has the potential to be pretty bad).
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