Arrange reclaimed boards of any type of solid wood on their long, wide surfaces and parallel to each other so that they form a 36-by-36-inch square. Cut the boards to fit, if necessary, with a saw.
Lay additional boards across the frame boards, perpendicular but flat, so that all of the original boards are overlapped by at least one of these cross-boards. Drill two holes through each cross-board and into each bottom board. Attach the boards together with 1 1/2-inch wood screws or whatever size of wood screw will securely connect the boards together without coming through the other side. This is the armrest panel.
Repeat Step 2 with another set of reclaimed boards to create a second armrest panel.
Repeat the armrest panel process with more boards to create a 36-by-80-inch panel. This will be the rear of the sofa bed.
Position the three panels in a U-shape with the rear panel in the back and the armrest panels on either side of it. Have an assistant hold them in place.
Set an old door or a similarly-sized panel or reclaimed board up against the U-shaped panel arrangement. Hold it about halfway up the panels. Position 3-inch L-brackets against the underside of the door against the panels and secure them in place with 1-inch wood screws. Space the brackets every 12 inches.
Attach L-brackets against the top of the door. Add brackets, as well, between the rear and side panels underneath the door to keep them out of sight and behind the frame, if desired, for additional stability.
Apply a dark, reddish-brown stain to the assembled sofa bed frame if desired. Apply the stain with smooth, even strokes of a brush. Let the first coat dry for two hours then reapply additional coats in the same method until the desired color is reached. Apply a polyurethane coat to the dried stain with the same procedure. Let it dry for two hours and reapply at least three coats. Let the bed frame dry overnight.
Cover the frame with a mattress and bedding that reflects an Indian theme, with bright, rich fabrics. Rich brocades and madras are also appropriate, as are tassels and fringed, silky material.