You take a battery and you attach each end of a wire to it then you wrap a peice of iron in the middle of the wire.

get an nail wrap insulating wire around the nail( the more times you wrap it, it stronger it is), then connect one end of the wire to the positive end of a battery and the other to the negative end.

This should tell you all you want to know. :) just copy and paste this to you address bar. This is a link to some videos explaining how to do this! http://www.youtube.com/results?search_type=&search_query=how+to+wire+wrap+jewelry&aq=2&oq=how+to+wire+wr

This is a description of a transformer.

Since the wire gauze is a good conductor of heat, all the heat is sttracted to the wire gauze