Stack both sets of doors on the work surface so the top and bottom of the doors are even. Stack the doors so the hinges for each set of doors is on the same side of the stack.
Look at the side of the stack of doors opposite the hinges and you will see the four edges of the doors.
Measure 1 foot down from the top and up from the bottom on the two center door edges and make a line at the measurements.
Open one hinge and line the top edge of the hinge with a line on the edges of the two center doors.
Hold the hinge with one hand and attach it to the door with the included screws using the drill.
Repeat for the other hinge.
Stand the doors on end and paint, stain or decorate as desired.