Compositing tips for Photoshop

So I did a photoshoot of a steampunk model and I want to composite a prop into her hand which I made in blender.
I would love to hear from you who have experience about any tips you have for blending CG elements (props, backgrounds, objects etc.) with real photos and how to make them look real. Things like lighting, masking, and other tricks to make it more photo realistic.

My model held a broom stick as a place holder, here is my prop: