Here is the one I use, patterned after Brad Merkel design. It adds box sides to the lower spreader for keeping tools in use. 2x8 for top and ends, 2x4 base for more stability. Top overhangs for ease of attaching and removing vise. Magnetic plastic vise jaw inserts for gripping wood without marring (I have also used thick leather glued to the jaws for this but it tends to come off with use).
Sand the seat area to reduce splinters. Round the corners so the vice handle will work in all positions.
Materials: (Used) 2x8 top and ends, 2x4 for base, 1x8 for spreader (on top of 2x4's) and 1x4 for box sides, (New) inexpensive 4" vise & mag jaw pads, screws to assemble.