How to set up a Salesforce integration
First, navigate to the campaign where you'd like to connect the Salesforce integration, then click "Integrations" from the menu on the left side of the screen.
Click on 'Salesforce' in the list of available integrations.
Next, either search Salesforce in the upper right search box, or click the Analytics category, then click Salesforce.
In the next window that appears, enter the domain for the Salesforce org that you would like to connect, then click "Continue". This article from the Salesforce knowledge base provides details on where to find your domain name within their interface.
Please note that you'll only need to enter the subdomain. For example, if your org's domain is https://mycompany.my.salesforce.com, you'll only need to enter "mycompany".
You will then be sent to the Salesforce login page.
After you enter the login credentials, the integration will then be connected and your client's Salesforce metrics will be imported and displayed within their campaign.