Note: i Tried this by myself and its working 100%
all you need is this programe :
Sorry, but you need at least 25 posts and 5 hours online time to unlock hidden content.
After you download it, install it.
>run steam and click on log in with your steam account
>it ll start working, just leave it and do whatever u want,
>after you run it, it ll show on your steam status that u are playing .
After that u ll recive your Cards
>>>it might take alil time