This will keep junk mail out of your normal inbox. They may say they won't sell your information, but less-reputable companies might give it away for a favor. Once your information is out, it's out. You will usually be required to provide basic information such as your name, email address, birth date, gender, and address. Later in the process, you will also need to provide PayPal information—usually associated with an email address—so that you can receive the money you’ve earned. This is a good time to review the Terms and Conditions and Privacy Policy if necessary, as you will be asked to legally agree to them. After registration, companies will email the email address you’ve provided to verify. Open this email and activate your account to confirm. If an incoming address doesn’t match one in your address book, your e-mail account might mark it as spam automatically.

Summary:
Make a dedicated email account just for surveys. Register with legitimate companies. Check your email to verify. Add the site’s email address to your address book.