How to place a molecule above the surface at desired distance and orientation


I have a 6x6x1 supercell of graphene which i have optimized. Separately i have a H2O molecule, which is also optimized.

How can i now place the H2O molecule over the graphene surface? I want to place the O molecule over one of the carbon atom at a distance of 3.31 Angstroms. Also the two H atoms should be legs down (i.e bent towards the graphene surface).

I thank you in advance.