If you are already signed into TripAdvisor, click the blue Connect button at any time. You should see the button at the top-right of every TripAdvisor page. If you are signing up for a new TripAdvisor account, click Sign Up in the top corner of any TripAdvisor page, and then click the Sign in with Facebook button.How do you login to Facebook?
Login to Facebook and click "Account" on the menu navigation at the top right of your screen. Scroll down and click the "Account Settings" option. Find the Settings tab in the My Account section. Once this is confirmed, scroll down to where it says Linked Accounts and click "Change.".