Add a Symmetry Constraint

  1. Select Sketch | Constraints | Add symmetry constraint.
  2. Select the first line or point.
  3. Select the second line or point.
  4. 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.
  5. Add more symmetry constraints by repeating steps 2-4 or finish adding symmetry constraints by pressing the ESC key or the middle mouse button.