Contextual audiences can be created through Audience app.
Open the Audience.
Select Contextual Audience from the left panel or for first time customers, right panel will also have link in the right panel with some information sections.
Context could be set on Keyword or URL levels.
Adding Keywords
Keywords can be added by typing or via file upload.
Keywords can be selected by type ahead feature , it will show similar looking keywords
Once we add the Keyword, you will also find recommended Keywords , out of which you can add more.
All added Keywords will appear in the right pane
Adding URLs
Select URL tab.
URLs can be added by typing or via file upload.
Once URL is typed, you can also see the preview of that URL
Once you are done with adding all contextual Keywords and URLs , next button will be enabled and will take you to the next step of this process
In this step you need to give audience name and click on Create audience. You can also see a summary count of URLs and Keywords added in this contextual audience.