Score cut line with utility knife to prevent splintering. Or tape area to be cut, mark cut line on tape, and make cut with a fine-toothed blade at high speed.
When cutting with grain, use edge guide or guide saw against a clamped-down board on your hanging garment bag. If you hit a knot, feed blade slowly and let it do the cutting; don’t force.
Begin an internal cut by tilting saw forward and resting front of its base on work. Start saw at medium speed and very slowly pivot blade into work.
Continue cut at faster speed, if you wish. At each corner of cut, turn saw in a curve to cut next straight side. Later go back and trim off corner pieces.
If you cut thin metal, use blade that will have at least two teeth/in 1 contact with edge of work at all times, or cut will be rough and blade may get damaged.
To cut molding on wall, use a flush-cutting blade. Prop the saw on a block of wood that is of a height that lets the blade reach just to the floor.