Step 1: Disassemble tablet
Very carefully pry the casing apart (using a flat screwdriver to gradually pry up the edges helps). If you're using the tablet I did (the Wacom "Bamboo Fun") you can pull out the scroll touchpad from a little plastic slot but BE CAREFUL! I damaged the connections when pulling mine out and ended up breaking the touchpad. Carefully remove the board and the insulating metallic sheet behind it.
I really ought to have more pictures for this step, but I disassembled mine a long time ago. It's pretty straightforward, but let me know if I can offer any assistance.