You should never give the hummy a bath. If something is stuck in his fur, on the surface, just get an adult to give him/her a haircut, or just using a damp cloth clean him/her up. Another option is the sand box, but never never water.
This is very serious as I understand, you can kill the hamster this way. They are so small and they need to keep a certain body temperature.
If you have no other option, water baths are fine WITH PRECAUTIONS. Lukewarm water, enough water for the hamster to WALK in, and a very short bath. After the 5 minute or less bath, you dry them for at LEAST 10 minutes to ensure COMPLETE dryness, and then give em' a nice treat for being so good while they sit in their house ;) You can't really cut a dwarf's fur, and if the hamster tries to groom, it will ingest toxic material.
Edited by bobthealien, 16 January 2013 - 08:15 AM.