If I want to have a class in someone's home teaching home improvement skills, how do I avoid liability?

Contractual liability limitation and insurance are two very different things.  The best way is to do both - have a comprehensive contract that minimizes your liability and have insurance coverage.  You should also provide the teaching via a separate, incorporated entity such as an LLC.  Done properly, that will preclude liability (mostly) for you personally. If you would like to discuss any issues further, please feel free to contact my office.  The link to my contact information is below.  Thank you. The foregoing is general information only, not specific legal advice. No attorney/client relation has been created or should be implied.