There are many ways of developing fingerprints, below is one experiment that uses iodine as a method of developing fingerprints.
You will need: filter paper; a paper clip; iodine crystals
1) Make a fingerprint on a small piece of filter paper by firmly pressing down.
2) Take a paper clip with a piece of string attached to it and clip this on to the filter paper. Place a few iodine crystals on the bottom of a screw top jar.
3) Hang the paper clip and filter paper inside the jar and put the lid on tightly trapping the string out the side of the jar and suspending the paperclip and filter paper.
3) After about ten minutes, the iodine will develop the print on the
filter paper and the image should be clear enough to photograph.
Alternately, fingerprints can also be easily revealed by brushing a fingerprinted surface with iron filings or lifted from a surface with adhesive tape - neither require 'developing'.