To start VO-SWMM, simply double-click on the VO desktop icon or find the VO item from your Start menu. Once VO-SWMM starts, you will first see the splash screen as below

Then, you will see the main window. You may see the main window as below, which is used for the Visual Otthymo project.

Switch to the main window for VO-SWMM. Navigate to File -> New Project -> New SWMM Project.

Your main window will change to the interface for VO-SWMM project. Click on the Map tab to see the Map view, which by default displays the map of Toronto, Canada.