Where you mount your trail camera is dependent on the situation. When it's late in the summer, for example, deer are still using warm season food plots. Anytime you can find trails or travel corridors coming from bedding areas to food sources, those are the best places for mounting a trail camera. You have a good chance of getting pictures of bucks in velvet or does with fawns.
It's a good idea to camouflage your game camera with surrounding brush so potential trespassers won't see it and to keep it out of the deer's face. Just make sure no limbs or leaves are in the field of view.