Play games
Choose the game that interests you and play itfor free.
Complete the quests
Every game has some quests for which you will receive Soul Gems.
Receive rewards
You can exchange your Soul Gems for Steam Wallet top-ups, game keys, CS:GO Skins and other rewards.
The first task fir Desert Operations is currently broken as the game has renamed the achievement to "I Have Friends" instead of the acievement listed on the task "i am am alliance memeber"