Frame:
To make a bed in your car you will want to find a few long 2x4s and a large sheet of plywood. Start by taking out your cars rear bench seat(s). Then take your tape measure and find the dimensions of the whole back area (seat area + feet space). Cut boards to run parrellel and create a square ( much like a wooden barrier of a garden). Then decide how high you want your platform (level with trunk height but not to high that you loose head room). Cut 4 pieces of 2x4 with your desired high and install them vertically. These will be the platform legs. From there flip the entire thing upside down and rotate to fit in the back door of the car. Press down untill the frame lays flat and is secure.

Bed:
All that makes up the bed is measurements around your back seat (seat area + feet room) is a piece of plywood cut flush to the backseat.

Supplies

Miscellaneous wood (2x4s, plywood)
Screws
Tape measure

Step 1: Cheap Car Camper From Old Sedan

Welcome to my instructable on converting your car into a camper. It is just the general idea and cover some basic things it won't work on ever model (obviously).

Step 2: Kitchen

I took the spare wood pieces and made a frame similar to the step above (only difference is the measurements, witch match my trunk) then I took an old door hing and made a "counter" like space on top of the frame that can be lifted, allowing for more storage underneath. I use the storage for a camp stove, food, utensils and propane.

Step 3: Back Seat Bed

I'll make this short and sweet. To make the bed in the back seat I simply reinserted the cushions that were there before but in reverse order. (Seat was the back and the back was the seat). Blankets can be stored under the cushions if you don't like them left out.

Step 4: Extras

I store my food in a container with rodent proof lock and store a folding chair in what trunk space is left. If you guys have any ideas on how to improve this design please leave a comment.