Understand your client's and their competitor's creatives, messaging, publishers, and user acquisition networks.
Analyze your client vs. its competitors in the Competitive Analysis tool and go to Display Ads > Creatives & Videos to understand the messaging of the creatives that your client's competitors are running.
Navigate to Publishes to get insight into what placements they have used in their campaigns (where the creative banners are published), navigate to Publishers.
TIP: Pay attention to the Total Traffic Share column, where you can understand how much display traffic was generated by each publisher website
Use the "Networks" and "Industries" filters at the top to narrow your search results.
Navigate to Ad Networks to discover which networks your client and their competitors work with.