Step 1: Get a book!
Step 2: Finish Compartment One
Step 3: Compartment Two
Step 4: Build the 'secret' feature...
1. Radio Shack (or other brand) voice recording module.
2. 9 volt battery
3. SPDT Lever Switch
4. 1/8" Phone Jack
Remove the button attached to the circuit board by peeling back the three clips that hold it in place. Then solder two wires to the contacts on the circuit board and solder the lever switch to the other ends. Be sure to use the N.C. or Normally Closed contact.