After logging into the site, navigate to "Layout > Block Layout"
At the bottom of the Block Layout page, you will see a list of "disabled blocks".
These are blocks that are not currently in use on the site, but can be added.
After created your Ad Group, you should find a block similar to "Ad Group: (ad group name)"
Drag the block, or select from the drop-down, where you want this ad block to be viewed.
Based on the ad style, you may want it above or below content, or in the ad sidebar.
Make sure to click "Save" before leaving this page.
If your ad is not visible, you may need to get your permissions updated by the Our Hometown team.