Complex sentence: When the saw is set up for a cut, the operator raises the saw by hand and the material is clamped in place and the saw is turned on, the blade slowly descending into the material, cutting it as the band blade moves.
Split into simpler sentences: When the saw is set up for a cut, the operator raises the saw, positions the material to be cut underneath the blade, and then turns on the saw. The blade slowly descends into the material, cutting it as the band blade moves.