Mouse + keyboard. After the first point you can type exact measures and press Enter: Line = length, angle; Rect = width, height; Circle = radius; Arc = radius, start angle, end angle; Dim = offset; Copy/Move = distance along cursor direction; Offset = distance; Mirror = angle; Rotate = center, reference, destination (or signed angle after center + reference). Trim = click the segment to remove (line, arc or circle); Extend = click near the endpoint to extend (line or arc): both search automatically for the first useful intersection. During drawing, hover near an existing point to acquire temporary X/Y tracking guides; acquired guides combine with current axis guides and can snap to virtual intersections. Delete and Ctrl+Z also work.