Position the bevel gauge so that one arm is parallel with the last row of flooring and the other arm is parallel with the angled wall. Tighten the wing nut on the gauge to lock the angle into place.
Place the bevel gauge on flooring so the straight edge is aligned with the outside edge of the laminate and the angled arm extends onto the top. Mark the angle with a pencil.
Align a ruler with the angled marking and mark the angle along the entire diameter of the board.
Position the marked board in the miter saw with the angle marking under the blade. Adjust the miter saw's angle by pushing down on the locking mechanism and rotating the blade with your hand. Align the angle of the blade with the angle marked on the board.
Cut the board along the marking by pulling down on the miter saw while holding the board against saw's fence. Make sure your hands are clear of the blade before cutting.