You can select the card from the first page of the game, above the Start Game button. We support the National Mah Jongg League 2019, 2020, 2021, 2022, 2023 and 2024 cards, as well as the I Love Mahj card. Click the 'Change Card' button and choose the card you wish to play with.
Note that if you're playing with other people, the table leader sets the card for the table. If you're not the table leader, you will see the card selected in the same spot but will not see the "Change Card" button.
For exercises, you can select the card at the top of the screen (or on the first page for the Charleston Practice exercise).