Play games
Choose the game that interests you and play itfor free.
Complete the tasks
Every game has some tasks 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.
Do you want more exp? Then do this:

1.Everyday type a maximum of 5 comments.
2.Be writing few forums.
Anyway that is all I have for now on how to get exp, bye bye.
XD.