shredded or powdered caapi is the way to go.
for both mhrb and caapi you do 3 boils (minimal water, but not too little) for about 30 mins (really until the water can take on no more color which sometimes takes longer, but at least 30) filter, combine, and reduce.
i prefer to do the force and the light in seperate boils and drink them seperately. also with both of these plants i like to to a fining of some sort (egg white is probably the easiest, but any gelatinous protein should work). as far as dosage goes you are looking at 3g mhrb and 50g caapi (ish) but i would brew 100g caapi and 6g mimosa and just drink half (more if necessary).
reduce the brew to a small amount (i like about a third to a quarter of a shot per dose, but then i refill the shot glass with water to get the remainder), and get some ginger or something on hand to prolong the nausea so you don't purge before you absorb the medicine.
also sage and incense and what not are good as well.
♥ i hope you enjoy your experience ♥
EDIT: you should really look at some of the stickies and other threads in the ayahuasca subforum, TONS of info in there, best of luck.
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