The most effective way to get rid of mosquitoes is to stop them from being able to breed. Mosquitoes lay their eggs in sources of standing water, so reducing the amount of standing water on your property can dramatically bring down the number of these dangerous pests. Make sure that any tires, buckets, or other objects that could collect water are emptied and stored somewhere under cover. Replace the water in your swimming pools or ponds on a regular basis.
If you have a pond, you can introduce irrigation, and add fish to the pond that are known insect egg eaters. Gambusia, green sunfish, bluegills, and minnows are all great choices.