Multi Click allows you to select multiple clickthrough destinations in one ad set.
Once you finish building the ad, click on "Get Tags". Then click on "Generate New Tags".
On the next screen, you have two options:
You can choose to have only one URLfor the whole ad.
Or you can check the box labelled 'Creative Components) and have multiple URLs in the ad.
In order to better understand where each URL will be placed, turn the option "Show Labels" on.
The dots under the ad represent each slide of the ad. All slides have clickthrough URL destinations in it. Click on each dot to edit the URLs for all slides.
Once all URLs have been placed into each slide, you can choose between save and get tags or just save the changes.
The eye icon represent each label being displayed in the slide you're editing.