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 prologue for part 2 has been released! Instead of a new section to show off the new stuff, most of the FGO NA website has been locked down. Check it out yourself:
https://fate-go.us
Also came with new stuff is new requirements. If your phone has been barely able to run FGO till now, might be a good time to get yourself a New Year's present. The new servants' NPs are quite fancier than the current ones.