In order to display calendar events on your watch, you need to have the corresponding calendar app installed on your phone. Then open the Vector Watch app on your phone, select the watch face in use, tap on streams, hold for a second and drag the Events icon to the watch face. The next event will be displayed on the relevant watch face in about 10 minutes.
On specific watch faces, typically analog ones, you can have an overview of your agenda by pressing the middle button. This will activate an outer circle that highlights your upcoming appointments throughout the day. A meeting will show up as an arc of a circle, for example.