First, navigate to the campaign where you'd like to connect the Trustpilot integration, then click "Integrations" from the menu on the left side of the screen.
Click on Trustpilot in the list of available integrations.
Then click "Connect New Account".
In the window that appears, you will be asked to enter your login credentials. Once you've entered your credentials, click "Sign In".
If the client that you would like to connect is under a different Trustpilot account, you will need to enter different credentials to access that account. To do so, click the button that says "Switch Account" and follow the above steps.