Step 1: Background: Super Glue (cyanoacrylate)
When using cyanoacrylate glue for fingerprint fuming, it is important to keep in mind that these glues have a short shelf life of about one year from manufacture if unopened, or about one month once opened.
1. The vapors of cyanoacrylate are toxic (http://en.wikipedia.org/wiki/Cyanoacrylate#Toxicity). Take the appropriate precautions to avoid accidental inhalation.
2. Super glue bonds to skin quickly and can easily stick your fingers together. If this happens you can soften the glue with a solvent such as acetone (nail polish remover).
3. Cyanoacrylate reacts strongly with cotton or wool and can burn skin.
Step 2: The Heating Element
I recommend using a small 15-20 watt coffee warmer/candle warmer as the heater. Using a larger heater in a small closed space filled with combustible vapors can be a fire hazard.