Take your geometry and repeat it mirroring with a plane.
                      This modifier said I was the prettier so get lost with it.
                  
                
                
                Parameters
                
                  - 
                    Mirror Position (3D Position) : Position of the mirror
                  
- 
                    Mirror Rotation (Euler Angles) : Rotation of the mirror
                  
- 
                    Offset (3D Position) : Offset of the reflected object
                  
Presets
                
                Standard Presets: Mirror X, Mirror Y and Mirror Z