Here is a link to some contracts: http://mashable.com/2014/06/30/free-contract-templates/#S9fKy.gXbmqs
Here is an example of one: https://s3.amazonaws.com/bidsketch-ds/resources/contracts/web-design-contract-template.zip
Use lucid chart to make a visual of your site to add to the contract.
Check out and use Google web dev tools. https://www.google.com/analytics/#/small-business
Check out how to get your Business license: http://www.cityapplications.com/business-licenses/CA-California/biz-California.html
Check out how to start an LLC: https://howtostartanllc.com/california-llc