Here are the steps necessary to continue editing a draft email:
    1. Click EMAIL tab on top
    2. Check email that is under Draft status > Click Open
    3. Click Back at page bottom of Edit email 
    4. Continue editing email contents
Note: Further edits are not allowed once an email is sent. It is highly recommended to select Save as template to save your draft as a regular email template for future use. Click to learn how to Create New Template Using Premium Email Tool