Here are 2 quick renders; the first has no AO, and the second has AO.

                                                            

                                                               

                      

The last image contains the additional nodes for ambient occlusion. Distance controls the spread of the occlusion.  The DiffuseBsdf node changes the color of the shadows. The shaders are based on EZSkin.

If you are using the PhysicalSurface node for Superfly, I have also worked out the shaders nodes to create a rough AO map.  It is not perfect, but it does the job.