I would start here:
Banner by @Yili What is the trading card game? We are excited to announce the Kpopsource Trading Card Game! By completing certain activities you will be able to earn cards of different Korean Idols/Artists, International Artists and other decks such as Anime/Video Games. Once you receive the...
kpopsource.com
But basically, you can request a card every day (as timed by KST) for each daily completed (max of 2). And you can request a rare card every week where you do at least one daily at least 6 of 7 days. You can also join the cards taglist (
here) and be notified when there is a free card day, where you can request a card with no additional requirements.
Since you're a STAY, I would recommend you request from Korean 2, Rare 3.
You can get into trading, the roulettes, and such if you want, but not everyone who collects cards bothers with those either. At the easiest level, it's just participating in the community and requesting cards once a day.
You can always ask for help here:
Rules All trades are final. You can discuss with others in the trading conversation thread, but once you post in the official trading thread there's no turning back. Do not harass others for cards that you want. Doing so will cause you to lose the privilege of participating and may earn you a...
kpopsource.com