Choose the type of geometry (polygon, quads, ...) to be constructed and displayed from the selected vertices by pressing its radio button.
You choose the current (vertex) color by pressing one of the six radio buttons provided for this purpose.
The standard colors that are provided are red, green, blue, yellow, magenta and cyan.
You can also cycle through these six colors by pressing the radio button Cycle Color.
Observe a color is associated with a vertex and vertices may have different colors. Therefore, the tutorial is constructed so the current drawing color is applied to the "next defined" vertex versus changing the cover of a previously defined vertex. This approach is consistent with how OpenGL works.
First click on the radio button "Custom Color" under the category "Select Color." This allows interaction on the parameter input window.
Two radio buttons are provided for selecting one of the two shading methods - Smooth or Flat.
Two radio buttons are provided for selecting one of the two ways in which the geometry is displayed - Fill or Line.
You have three choices for which faces are culled (not displayed) - Front, Back or Neither.
This option means the points that you have selected will always be displayed and are drawn in white. You make this selection by clicking on the corresponding checkbox.
Not only are the vertices cleared but also all choices are reset to the initial ones.