Time to gather the stuff. You'll need:
A magic marker, probably crayola, since the body is wider than others.
A cheap pen. try and get one that narrows towards the end, but it's okay.
1 push button switch. Maybe a slide switch if you want.
1 small buzzer. the round case type is important; make sure it will fit inside.
1 audio jack, female. this will be used to recharge whatever small battery you can cram inside.
1 power source. get a small rechargeable battery, or a supercapacitor. It took me some time to find one.
And, most importantly, a Tirefly. It's a little bike light that clips to the wheels somehow; it has the perfect shape for the screwdriver head. Substitute something else if you have to. You can buy a set here
Get some scissors, a craft knife, and some pliers. Also superglue. And a drill. Plus the regular soldering stuff.