Two — one to screw it most of the way in and the other to give it a surprise twist at the end.
or
By carving a Trumpkin.
or
Two — one to change the bulb, and one to write a song about how good the old light bulb was.
or
Because it goes good with chips.
or
I rang her up, I said "Did you get my drift?".
or
Three: One to screw it in, and two to talk about how much better it is than with a man.
or
Six. One to turn the bulb, one for support, and four to relate to the experience.
or
Two, one to call Daddy, and one to get the (pick one:) mineral water/Tab.
or