Using the User Interface (Button): In the visual editor toolbar, click the Add Transition button (swap arrows icon).
Using the Command Palette: Run AutomationView Sequence: Add Transition or press T.
Divergences: To branch the flow, right-click a step and choose Add Divergence OR for alternative (selection) paths, or right-click a transition and choose Add Divergence AND for parallel (simultaneous) paths. Divergences are available from the right-click menu.