On initiating interactive drawing of curves, the cursor will change to a cross and indicate the Default Edit Plane. Left-Click to draw the first point and a line will be drawn between the clicked point and the cursor. Subsequent Lift-Clicking will add further points and line segments to the curve. In the case of NURBS representations both the curve and the control polygon will be displayed once there are enough points for the initial order (usually cubic - 4). To complete the curve creation process Right-Click. Curve drawing can be cancelled at any point by pressing Esc or by Right-Clicking with only one point entered.
The SnapToGrid and SnapToObject features can be used to provide additional assistance in the creation process and can be turned on or off from the Status Bar or from the PolyCAD Options Panel -> Manipulation Options. Points created using the SnapToObject may lie of the Default Edit Plane.