Add a Symmetry Constraint
- Select Sketch | Constraints | Add symmetry constraint.
- Select the first line or point.
- Select the second line or point.
- Select the symmetry axis. The line or point that was selected last moves so that it is symmetric with the first line or point about the symmetry axis.
- Add more symmetry constraints by repeating steps 2-4 or finish adding symmetry constraints by pressing the ESC key or the middle mouse button.