There are enough bacteria already in the lab, we do not need any additional ones floating around. Diarrhea is not pleasant. You also should wash your hands as you leave. Your roommates may not appreciate unwanted guests. Plastic gloves are available for you to wear, and they are reusable.
Soap is found by the sink in the lab.
When done with an agar plate, you should tape it shut and place it in an autoclave bag for disposal. Place tubes containing media in the rack next to the sink and empty tubes in the white bucket by the sink. Used wet mount slides also are to be placed in the white bucket. Any slides used for staining should be thrown-out in the broken glass box. You have the entire semester to do these, but once you hand them in for a grade, that's it.