Your code may now look like this:
Log in to your AdGlare portal, click Zones.
Add a new HTTP 302 Redirect Zone, give it a name and save it.
Click on the blue button at the top right to get the Ad Tag (which is a URL in this case).
On your page, replace the URL with this tracker URL.
In your AdGlare portal, click Campaigns
Add a new HTTP 302 Redirect Campaign, give it a name and save it.
Browse to the tab Creatives and add a New Creative.
Give it a name. Use as a Landing URL the original URL where your PDF can be found.
Click the Display Network tab, and select the PDF Download Zone that you've created before.
Save the campaign and wait up to 1 minute.