For the rules of k2, see GameHelpK2
Deduce the possible cards you may use in the next few rounds
As each player has the same set of 18 cards, you can deduce the possible cards you may use in the 1st-6th rounds, 7th-12th rounds, and 13th-18th rounds.
At the start of the 1st, 7th and 13th round, copy the following text into "My personal notes on this game" on the upper-right corner of the BGA interface. Then, delete the cards you have already played in the following rounds.
Green: 1, 1, 1, 1, 1, 2, 2, 2, 3, 3, 1|2, 1|3, 2|3
Blue: 0, 1, 1, 2, 3