Using a 58″ 2×4 – secure it to the studs on your wall. Determine proper work bench height for the person using the workbench. Good rule is the height of where your wrist bend (crease).
Center table top on top of 2×4 cleat and use a stool or table and build up other side so the table is level. (temporary)
Use 3 heavy duty T-Hinges (FLAT) with proper mounting hardware and position the hinges at a 90 degree angle and mark for pre drilling of holes on table and cleat. Space the hinges out evenly.
Take Gerton table top off and pre-drill hinge holes and mount the hinges. Also pre-drill the 2×4 cleat as well.
Mount the leg hinges (either vertically or horizontally at the other end of the table depending how tall your table will be. If the table is greater than 28″, I would mount horizontally as the legs will not fold in.
Place back the table top and secure the hinges with proper hardware.
Use 2 2×4’s and make legs for the 2 folding hinges. Always use a level for proper installation of the legs. I would trim a little over the height of the legs and do micro trims to get the legs just right. Once legs are properly trimmed (miter if necessary for uneven floor), secure with proper hardware.
When the work bench is finished and upright the weight should be supported by the cleat and the legs.