Instructions
Left-click on any unit on the screen that is under your control to select it, or hold down the left mouse button and drag a net over multiple units to select several at once.
Hold down "Shift" and then click on the "Attack" icon in the lower-right corner of the screen. Do not release "Shift."
Left-click the point on the battlefield where you want to set a waypoint for the unit. Click the "Attack" icon again, and then select another waypoint on the battlefield to issue the next travel command.
Continue to add waypoints like this until you have plotted the entire route for the unit, and then release "Shift."