1. Click "Campaigns>Campaigns" in Platform
2. Find the campaign in the list and click on the name to open the campaign
3. Click the button in the upper right corner and select edit
4. On the next screen click next in the lower right corner of the screen
5. Scroll all the way down the next page and click "Save and Configure Email".
6. The email editor will load on the new page and from there you can make the edits that are needed, make sure to click "Save" in the upper right corner of the screen when done.