Draw the outline of the weapon you wish to make to scale. If you wish to make a sword, axe, gun or spear, simply draw out the outline to use as a template.
Trace this outline out the wood you wish to use. Plywood, at least 1/2 inch thick works well.
Cut out the weapon following the outline using the jig saw.
Cover surfaces of the weapon that are meant to resemble polished steel with tin foil, and paint others black for blued metal or brown for wood, such as with spear or axe handles.
Shaping and contouring these weapons is possible if you want to make them as realistic as possible. Add edges or decorative elements by adjusting the base plate to cut at an angle, or through sanding. Glue on extra elements like feaux jewels or leather accents to give the weapons a more three dimensional effect.