Motion sensor lighting is an obvious first choice. Nighttime predators such as coyotes fox and owls hunt during the night and are easily spooked just by the light turning on and off. Although this has worked in various situations for many people it's not always the end it all solution your looking for. Eventually, the predator will be hungry enough to ignore the light or at least make a mad dash towards the food in hopes they will get away with it.
Secure your chickens during the night hours to keep them away from predators. A predator-proof chicken coop must be strong enough to keep the local hungry animals out. Dogs and foxes can tear through thin material easily. A determined raccoon will undo your latches, they are smart creatures too! Using 2 step latches really helps. Keep in mind a raccoon can open the same locks a 2 yr old can. Close up any small holes snakes, mice, rats or weasels may be able to enter through. These guys will eat your eggs and not stop coming back even if they have been relocated.
Chicken wire is an awful way to predator-proof a chicken coop. Chicken wire is very thin it is designed to keep the chickens inside, most animals can easily tear it apart from the outside. Instead, use 1/2 hardware cloth were necessary to keep out small animals like mice and snakes and livestock fencing to keep out the bigger predators. Keep in mind that some animals like fox and coyotes can easily dig a couple feet in a few minutes. extending the cloth or wire down into the ground usually prevents them from digging any further than the fence. My experience tells me that predators are lazy and will always go for the easiest food available and leave your chickens alone if they have to work too hard to get it.
A caged roof over the run keeps those pesky climbing and flying predators out. A predator-proof chicken coop can keep overhead threats away like owl, hawks and other birds of prey. Yes, birds of prey can fly away with your chickens. Even the Orpington Chicken which is a fairly large breed! In most cases, cheap netting will work unless you are having trouble with animals climbing over the fence and attacking your babies.
In conclusion, your location decides what it takes to make a predator-proof chicken coop. Different areas and settings have different predators and dangers. Sometimes an electric fence is required especially if your in an area that has bears and bobcats for predators. Not many animals will go any further than the first poke, it shocks them!