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.
It wants me to install it. Small amount of gems to gain. And boring game not worthy enough to get my download! xDDD But Wishing you best of luck