To create new edges:
Choose Insert Mode in the Edit menu, or click the Insert Vertices/Edges toolbar button or context menu item, or press INS, to switch model view into insert mode.
Specify the angle of the new edge in the New Edge Angle box on the toolbar. Use one of the predefined angles provided in the list, or type another value in the edit box. To create a linear segment specify zero angle.
Left-drag the mouse from the starting point of the edge to its end, or use SHIFT+DIRECTION keys. The ends of the created edge can coincide with the existing model vertices, otherwise QuickField automatically creates the new vertices as needed, so that QuickField, adding the new edge to the model, always connects two existing model vertices together. Switch on the snap to grid option (default), to force the new vertices on the current grid. Navigating with the keyboard, use the CTRL key to fine tune the points.