Use the outliner to construct an outline of general scenes, beats, and moments for your script. Move seamlessly between your outline and script because they are different views of the same content.
Outline lines are hidden in your main document, but can be toggled to be shown by selecting the "Show Outline" checkbox in the main editor's widget menu. You can always add Outline lines from your document view using the Outline icon or Command/Control+0.
Jump to a card, tag/color a card, focus on a card (so that only the selected card(s)' content are shown in the document), or remove a card, all by selecting the options in the upper right corner of each card. Click-hold-drag to move cards to new positions that will be reflected in the document. One can also jump to the position that a card reflects in the main document by clicking on the arrow icon or scene number in the top right corner.
Cards can be viewed and edited in the sidebar Cards widget, or fullscreen by accessing them within the Card Outliner by going to Tools > Outliner > Cards. Check the 'Use Outline Mode' checkbox in the Cards widget menu (checked by default in full-screen view) to automatically create Outline lines when hitting Enter from the first line in the card (usually a Scene line).
To add a card, select the + icon in the Cards widget menu or double-click in empty space.
Cards are in a left-to-right, vertically descending grid by default. Use the 'Allow free drag' checkbox to move cards freely around the space, and adjust their height/width independently by dragging the bottom right corner.
Note: To create an outline that isn't synced to the scenes from your main script, you can create a new Doc for your outline to live within your project by going to Docs > New Document. Switch between your outline and script in the Docs sidebar, and navigate to Tools > Outliner > Cards to view any document as cards.
P.S. We used to have a corkboard background image to make it feel a bit like pinning index cards for your outline, but felt like it didn't fit with the new aesthetic starting with version 5. If that's something you're interested in seeing, let us know at email@example.com!