Adding a widget
To open notification center on your Mac, click the date and time in the menu bar, or swipe left with two fingers from the right edge of the trackpad. Click ‘Edit Widgets’ button. Chose Numerics from the list of applications and select the widget size you prefer. The blank form of the widget will be placed on the right side of the screen. Click the blank widget to see the configuration options. Here, first choose the dashboard and then the widget you want to add. Now your widget is added to the notification center.