How to Set Overlay for a Specific Page
You can set a pop-up for a specific page by following these steps:
Click on the Campaigns category on the left side of your screen.
Click the Details link of the campaign you wish to edit.
Enter the page URL in the Base Url field. Check Apply to all site. Add parameters for URLs you want to show the popups to.
In this example, the popups will be shown only on "blog" pages of your website.