Step 1: Things you will need
1 some side cutters
2 some scissors
3 an old hard drive
4 a tin food can (I used a tuna can because it had flat sides)
5 tools to dissasemble the harddrive (varies with the type of harddrive)
Step 2: Open up your hard drive and recover the magnet
The magnets are usually glued onto a peice of steel with a couple of holes in it, if you have a modern car you may want to leave the plate on and use the holes to screw or cable tie the magnet to your dash
Step 3: Fit the magnet to your dash
You may neet to be a bit inventive using cable ties, double sided sticky foam etc.
Make sure the position does not interfere with driving, the cables are easy to get tangled up in! (so experience has taught me)
Step 4: Cut a piece of steel to fit inside your phones case
Cut a peice of steel from the side of the can using scissors, you will probably need the sidecutters to get through the rim, or else use a can opener to take the rim off.
As you can see from the photos I have shaped the metal to press between two plasic lugs on the inside of my phones rear case. If your phone won't do this you might need a little double sided tape to secure the metal.