Hold down the left mouse button over a card, and drag the mouse to another position on the window. Release the mouse button to drop the card.
You might wish to move several cards. To do this, select cards by left-clicking on cards while holding down the control key, or alternatively left-drag a rectangle from top-left to bottom-right encompassing the cards you wish to select. Selected cards are shown in reverse video. You can unselect the cards individually with control left-click, or all of them by left-clicking somewhere on the storylines window. When cards are selected, dragging one selected card will drag the others too.
You can right-click over a card to bring up a menu that gives you access to various commands.
Go to Step 4 to learn about saving your project and reloading it.