It should be pretty easy, like any compound bow. Take the right size allen wrench (3/16") and turn counterclockwise 1 turn at a time. Do each limb the same. Each turn reduces draw weight by about 3#. Don't turn it down any more than 5 turns, which should be about 15#.
This assumes that the limb bolts are turned all the way in to begin with.
By the way, welcome to the Tech Forum.
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