Step 4: Test, Deploy
Now here's the fun part: plug your apparatus into your PC, and see what it does.
In most cases you should be able to use your new device right alongside your "normal" keyboard, as long as you've got the ports (mine is USB, but a PS2 would work, too).
If the test is successful, package it up and call it complete!
I glued an F1 key to my device (from the donor keyboard, of course), and even though it will be stashed away inside my kiosk and never be seen, I like the idea that the F1 key is in there, silently advertising its silly purpose...
Thanks for reading!