Igloo have an dependency on Umbraco Forms, so on local or your own server installtions make sure Umbraco Forms is installed before installing the Igloo package.
The installation is a standard Umbraco package installation. Follow the steps below.
To activate your license put the Igloo.key file in the root folder of your site and restart the site.
Once you have installed the package you need to create the following node structure.