Lay a leg on a flat, even surface or a work bench.
Apply wood glue to the holes in the leg and around the ends of the dowel pieces which are to be inserted into the holes.
Insert the dowel pieces into the holes.
Apply more wood glue to the other ends of the dowel pieces and also to the holes of the opposite leg.
Align the opposite leg above the dowel pieces and gently hammer into place using a block of wood as a buffer so as not to damage the leg.
That is one end done. Repeat the process for the other end.
Lay the two end assemblies on edge on a flat, even surface, opposing one another.
Apply glue to the notches and the ends of a front or back rail.
Position the rail into the notches so that the ends of the rail are in 20mm (3/4") from the outside edge of each notch.
Fasten with three screws each end.
Note: Pre-drill the holes for the screws in the rails prior to fastening.
Flip the unit over and repeat the same action on the other side.
Stand the unit upright.
Measure from notch to notch for the required length of the end rails.
Cut the end rails to length.
Apply wood glue and screw the two end rails in place.
Note: Pre-drill the holes for the screws in the end rails prior to fastening.