1. Review product features to understand compatibility and versions.
2. Marketing Cloud Connect requires a relationship between a single Marketing Cloud account and one or more Salesforce orgs. Your Marketing Cloud account must be provisioned and enabled for use with Marketing cloud Connect before connection.
3. Subscriber Key is required for Marketing Cloud Connect. If it is not enabled in your Marketing Cloud account, complete a Subscriber Key Migration before proceeding with the connection process.
4. Ensure that four custom tabs are available in your Salesforce org.
5. To use most Marketing Cloud Connect functionality, users need a Marketing Cloud license and a Sales or Service Cloud license.