Board Game Arena

In the tutorial your cards are automatically sorted in ascending order. In the actual games how can you sort what you cannot see?

I don't know because I don't have the physical game, but I'd guess you deal out the hands, each player sorts the hand they receive, and then you simply pass the hands one player to the right (or left), and just don't look at the faces of your cards as you pick them up.

Haha, you mustn't read the rulebook:
+ Cards are dealt to all players.
+ Each player should FIRST sort cards in Color, then sort in values ascending or descending, everyone should synchronize this action.
+ Then, they will face down the sorted cards and pass them for other players clockwise or counter-clockwise, as long as everyone plays synchronized with each other.
+ Each player now picks up cards in front of them but do not turn them face up, so they don't know the values.

Then the game starts.