1. Navigate to Checkout Editor and click "Customize" for the respective Checkout
2. Click [[Add app block]] in the section you'd like to add the Customer Donations extension
3. Click "Customer Donations"
4. Click to go back & drag the app block to the appropriate location
5. Click to drag and drop app block below "Subtotal"
6. Click app block to update settings
7. Click the "Donation Heading" field if you want to add additional text.
8. Click "Save"!