Create and observe bacteria in petri dishes (and then under the 'scope) for my own learning experience. I thought I was being sufficiently sanitary while heating the agar and pouring it into the plates. But before I even got the chance to start up bacteria in one plate to isolate in the other (both plates were supposed to be sterile), there were many colonies growing in both of them. I heat up the agar by boiling it and I held the plates in boiling water just before pouring the agar into them. I try to open the covers a minimal amount while pouring the agar. I put a rubber band around each once I'm done pouring. I'm not sure what else I can do to get a sterile environment in the dishes. Any tips? Also, once I do get to putting bacteria in them, how will I do that sterilely also? I have inoculating loops that I'll sterilize before using but that also requires opening the lids.