Before installing the app you will need to ensure you have approved the installation of apps from unknown sources in Settings > Security.
You will have to download Z Launcher from the official site, instead of through the Play Store or a beta testing service such as Hockey App.
A long list of permissions that you must accept are displayed during the installation process. Should you not be comfortable with the level of access the app requires, you can always uninstall it.
After you've installed the app, you're reminded one more time just how much data the app will collect about you. The data is necessary to customize the user experience based on usage.
A brief tutorial will greet you after agreeing to the data collection.
Your apps are listed in alphabetical order, with no way to reorganize them. But if the app does its job, you won't even consider having to reorganize them.
More details on Nokia's Z Launcher are available here.