Onsite campaigns include: interactions, content and merchandising. You can test these campaign on your site safely, before turning them live for all users.
So check the Test mode box and below choose Active and click Save Campaign. Now the interaction will be running in test mode. Do not forget to Purge Cache to be able to see it on your website faster.
Clicking the blue link will go to the website and add a cookie. Having this cookie will allow the campaigns to be displayed and visible only to you!