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.
if you guys don't know, the source engine code got leaked and hackers have it on their hands. So if you are playing now the players can inject malicious code into you pc and could get malware and even get your personal data stolen. This is for every type of games that use the source engine. so if you are a TF2 or csgo gamer and are playing or just played you might want to run a security scan on your pc if not you might be in grave danger
TL;DR : source games are now dangerous, THAT INCLUDES EVERY GAME THAT USES THE SOURCE ENGINE. DONOTplay anygame that uses the source engine .(for user b4rn3y_)