Scenes organise your inbox based on the contents of the message, or who the message is from.
Big Mail will automatically move emails into the most appropriate Scene.
You can manually move a specific email into a Scene by long pressing on a message (on iOS) or right clicking (on macOS) and selecting “Move to…” then the Scene you wish to move the message to.
Sometimes you may want all messages from a particular sender to go to a specific Scene, for example your favourite writer should always be sent to your Newsletter Scene.
To do this, long press on a message from that sender (right click on macOS), and select “Always Deliver to…” then the Scene. All messages (past and future) will be moved to that Scene.