The clue is in the name:
DRY: It has to be BONE dry all the way through, not just on the outside
SIFT: Using a micron mesh filter, either in a frame or a tumbler, approx 125u to 160u for most tumblers, down to 70u for frames.
You shake your dried plant matter until the trichromes fall off and are caught by the micron screen. Check out AquaLabTech for filtration stuff....