An old telephone.
A 1cm piece of wood larger than your cell and the thickness of 18/20 mm.
A piece of plywood the same size.
A USB extension
Two USB ports taken from an old PC.
Open the phone and remove everything you find inside.
Draw a rectangle with a pen the size of the piece of wood. In my case for a Galaxy S is 80x135. If you need to delete all the holes in the cabinet you can enlarge the size of the piece of wood.
With the cutter or jigsaw removed the piece of plastic which will be glued a piece of wood.
Now precisely shaped hole that you made using a file and the piece of wood as a measure.
Place your phone in the center of the piece of wood and draw all around the profile sure to draw a little wider.
With the jigsaw cut out the inside, be precise in the cut.
Smoothed with sandpaper good for the inside that were cut. At this point you have to practice a slot to make room for the USB connector to charge the phone. Put the phone on the piece of wood and draw the quarry, cut it and sand it always with the jigsaw.
Take the piece of plywood and glue on the bottom of the piece of wood.
While everything dries prepare the USB ports. I took a laptop broke a piece of card with two ports, you must remove all the components soldered because the ports are connected to each other but there is no hardware that could handle and then create a short circuit.
Once cleaned and cut in the rear of the phone base to track and get an opening.