Select Symmetry Tools and select the symmetrical pattern you want to create. 

① Horizontal Symmetry

Create a horizontal symmetry pattern with the current brush. Drag the first icon to adjust the position of the symmetry line.

② Vertical Symmetry

Create a vertical symmetry pattern with the current brush. Drag the second icon to adjust the position of the symmetry line.

③ Diagonal Symmetry

Create a diagonal symmetry pattern with the current brush. Drag the third icon to adjust the position of the symmetry line. Drag the slider below to increase the symmetry lines to create a richer symmetry pattern.

④ Lock

To lock the symmetry line and click again to unlock it.

⑤ Hide

To hide the symmetry line and click again to show it.