More Accuracy with Keys
Using the Polygon Tool
To draw from point A to point B, which is at an angle, press Shift.
To draw from point B to point C, again press Shift.
When point C is clicked a second time, the polygon is drawn.
In drawing a polygon, sides are adjusted to level or plumb unless Shift is pressed.
To draw a polygon, click the vertices in order. When the last point is clicked a second time, the polygon is closed.