Place the wood block in the clamp on the work table.
Tighten the clamp securing the wood in place.
Place the jack plane atop the wood plank. Plane -- shave -- the board, starting with the end closest to you and moving toward the end opposite you.
Hold the front handle of the planer firmly with your right hand as you guide it across the board. Hold the rear handle of the planer with your left hand. Your motion should be slow and fluid while lightly applying pressure. As the blade cuts across the board it will produce shavings.
Re-position the plank in the clamp so that it extends beyond the table.
Place a handsaw at the upper edge of the plank.
Hold the saw firmly, moving it in a back-and-forth motion across the plank's edge. The teeth will cut through the board making sawdust.
Continue in a downward motion as you saw through the board. Hold the loose board, which is getting cut away from the larger portion, with your free hand so the wood does not split as you finish the cut.