Basic hygienic practices include: 

• Frequent hand washing, especially between, and after handling animals.
• Use dishes that can be discarded or cleaned between uses.
• Disinfect any tools you use.
• Removing poo, old food, etc.
• Quarantine new or sick animals.
• Care for healthy animals first so you do not accidentally carry germs from the sick ones to the healthy ones.
• Routinely clean the habitat with a disinfecting agent. Common bleach in a 1:10 to 1:20 ratio (using a quart of water, that is about 1/2 to 1 cup of bleach respectively), freshly made before use, works well. Allow to work for 10 minutes, then either air dry or rinse.

When you have a sick animal, it is a good idea to completely disinfect the entire habitat. Use a fresh bleach solution on all washable surfaces. Other materials can be baked, frozen, microwaved, or replaced to sterilize it. Most substrates should probably just be completely replaced. Live plants are rarely a concern, but they can be set out in sunshine to help disinfect them.

Edited 8-16-2012 (C) Mark Adkins