Hi, Chelsea, welcome to the forum. You start working with companies by signing up with them and then applying for assignments. The blue link at the bottom of the page, Official List of Mystery Shopping Companies, is a great list of companies to sign up with. I recommend signing up with as many as you can. You will go to their websites and fill out an online application, providing your SS# and personal information. Some will ask for a writing sample and others may ask that you take tests. You will sign a confidentiality agreement. After they accept you as a shopper, you will be able to search their job boards for jobs in your area. Best luck building and growing your mystery shopping business!