1. If you have not yet installed Steam, then download and run the installer:
http://steampowered.com/download/SteamInstall.msi
2. Create a new account on Steam, if you are not registered there yet.
3. Log into the system using your Steam account via an Internet browser:
https://store.steampowered.com/login/
4. Go to the "My games" section and select "Activate via Steam ...", read and agree with the Steam service subscriber agreement and enter the key received immediately after payment.
5. After that, the game will be displayed in the "Library" section, and you can download it from steam.
Crying Suns is a tactical rogue-lite game in which you play as an admiral of a space fleet and explore an empire that has fallen for unknown reasons. In this story-driven adventure inspired by Dune and Foundation.