Adding Campaign Member Related Lists to Opportunity

To add Campaign Member Related Lists to Opportunity, follow the these steps:

1. Go to Setup -> Object Manager -> Opportunity -> Page Layouts
2. Select the Opportunity Page Layout you'd like to update (you may need to repeat these steps for more than one page layout)
3. Navigate to "Related Lists"
   
4. Based on if you plan on using Account-Based attribution, Opportunity-Based attribution, or both, drag the appropriate related lists into your page layout
   
5. Click the wrench icon on the related list and update the columns accordingly. Here are our recommended columns:
   
6. Sort your related list by "Engagement Date" and choose "Descending"
   
7. Save your page layout and that's it!