Once you have created a diagram save it as a layout to be able to be used again. Think of layouts as saved reoccurring setups or max sets.
To save a set up as a layout click on the layouts button in the toolbar. Give your layout a name and click save. Now your layout will be an option when creating an event or adding a new diagram to an event. Get a visual preview of your saved layouts from Home.
Tip: Name your layout based on the number of objects and the setup style.