Okay.. I'll do my best to explain the way to make a lightbulb vap.

1. You will need a lightbulb (the clear ones work the best for this), a pair of scissors, two pen canisters, a 20oz plastic bottlecap, marijuana, and a lighter.

2. Take the lightbulp and cut off the very top of the metal part, above where the screw-in part starts. I use very sharp scissors to do this, but whatever you would like to use is fine, just as long as you can cut it off as cleanly as possible.

3. Using the scissors or some other type of sharp instrument, sort of punch out the "guts" of the bulb. This includes the filament, any wires, or any glass that is hanging down. This will give you a clean lightbulb "chamber". Rinse it out with water in case there is any dust or nastiness in there.

3. Take the bottlecap and punch two holes in it, each the size of one of the pen canisters.

4. Put the pen canisters in the holes, one pushing further out than the other, and then other one just sticking out about an inch.

5. Take bud and cut, break, crumble, etc it up as well as you can. You want it to be almost powdery so there is more surface area.

6. Twist the bottlecap onto the metal part of the bulb, so it screws on.

7. Hold your lighter under the bud (it should be at the biggest part of the bulb). You should see a slightly greyish smoke start to rise in the chamber.

8. When it's about full, you just inhale from the taller of the two pen canisters, and air should rush in the other canister, "shotgunning" it into your lungs.

Here's a pic that I made. I think it has too much detail.. but I really got into the MS-Paint action.