Applift integration

I want to use Applift for monetization of my free app.
I’ve found a tutorial here, Integration with Unity | AppBrain Documentation, but I don’t really understand . Can anyone that uses Applift help me? How do I set up where the add appears? Doesn’t Applift have an publisher key or something?

Hi
First of all, thank you for using our SDK.
We have a great step by step guide that exactly suits your needs in our Wiki.
You can find it here:
https://applift.atlassian.net/wiki/display/WA2/Unity+Quick+Integration+Guide
Pay attention that we also have the plugin for you to use.
If you have any Question, don’t hesitate to address us.

Applift Support