Toggle display/edit mode by clicking on the pencil

Reverse the stack of cards by clicking on the cycle arrows

Rearrange cards by dragging the header bar

Add a card to the bottom/delete the bottom card by clicking on the plus/minus

Save the stack of cards by entering a filename and clicking the "into" arrow

Open a saved file by choosing the radio button and clicking the "out of" arrow

Move a card to the trash by entering edit mode and clicking the X in the upper right or by dragging it to the trash

Empty the trash by clicking the "Trash" button

Delete all cards by clicking the X inside the trashcan