Easy:
1. Take a pen
2. Get the filling out of it
3. Take a cotton swab and cut it in half
4. Put the swab in the front of the pen
5. Roll aluminium foil at the pen, of has to touch the cotton
6. Tape the foil on the lower side
7. Put a drup of water on the cotton, jou dont want it to be to wet...
8. Try it out!