How to Draw 

Select the drawing tool that you wish to use by clicking on its button. Move the cursor over the video window. Click the left mouse button, and drag the mouse in any direction. Once you have moved the mouse so that the object is the desired size, release the button. The object will be drawn in the color and the line thickness that are currently selected. 

Certain tools such as the Spline, Angle and Posture are drawn in multiple steps. 

If you’re using a tablet and pen, pressing the pen firmly down onto the tablet is equivalent to using the mouse’s left button.