To organize your screens into sections, you'll first need to switch to manual sort via the ••• menu.* To begin organizing your screens:

1. Hover and click between rows of screens to create a divider. 
2. Name the sections. 
3. Then you can drag and drop your screens within the sections in thumbnail view. 

*If you see Use Alphanumeric Sort in the ••• menu, then you're already using manual sort.