First, sign into Squarespace and click "Marketing"
Then, click "Email Campaigns"
Next, click "Sent" so we can duplicate the previous campaign
When you see a previous campaign selected, click "Actions" in the top right
Then click "Reuse Layout"
Your previous campaign is now duplicated, and you're editing a draft. Add a subject for this email. The rest of the information should all be correct.
Next, click directly on the blog image (or text), and the right-hand menu will change. In that new menu, click "Manage"
After clicking "Manage," click the "-" icon in the red circle to remove the current blog post, and click "+ Add Blog Post" to add the new one
From the list that pops up, choose the post you want featured in this email, and click "Select"
Click the "Email" tab in the top right to get back to the main email settings, and then click the "Send to Mailing Lists" button whenever you're ready to send!