The following answers discuss how to
grow different kinds of bacteria. A variety of
microbiology laboratory manuals go into more detail.
The Micro Science Fair help pages has additional information, with descriptions, regarding specific techniques, equipment and reagents.
Strict safety precautions should be followed when growing bacteria, whether a known strain, or unidentified species from environmental sources. Pure cultures of otherwise "harmless bacteria" can become contaminated with potential pathogens. Likewise, bacteria cultured from the skin, mouth, sinks or dirt can be potentially dangerous if they get into cuts or in contact with mucous membranes including the eyes or mouth. Always wear gloves (preferably latex) and protective clothing (a lab coat and safety goggles) when handling materials and be certain to properly dispose of your experiments when finished.
We encourage you to discuss projects involving the growth of bacteria with your science teacher to make certain appropriate facilities for the growth and handling of microorganisms are made available to you.