When it comes to certain herbs, like Pau D' Arco, I prefer to soak them in alcohol for 30 days and then evaporate some of that on the changa to get it's essence in there without having to smoke wood and bark.
With the mullein, it makes a great base herb to infuse everything to because it's so sponge like.
As for everything else, like Parshvik said, it's all a matter of preference.
Just be careful when working with the extracts of stuff because it can get pretty potent pretty quick.
Also, it's not a bad idea to test your blends out by smoking some before you add your dmt to make sure it's not going to be too harsh or unpleasant. Once you've got a nice tasty blend, then add your spice and enjoy!
Good luck!
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