This image shows the Decisions editor.
On the left is the collapsed Services pane; on the right is the Diagram Palette.
The middle pane is your canvas for adding and defining decisions. There is also a toolbar at the top of the editor.
Three decisions that have been added are displayed. The What To Bring decision is the main decision at the top of the pyramid, and Temperature and Rain are added at the next level, with their outputs flowing into the main decision.
There is a widget at the bottom of the canvas displaying the minimized version of the current layout along with zoom controls.