If you have a spider problem in your home, don't be afraid to handle it yourself without calling an expensive pest control professional. You can do just as good of a job on your own.
Buying the spray
You don't need an expensive professional spray to keep the spiders out. Go to your local hardware store and buy some regular old spider spray. It really doesn't matter what brand you get, just as long as it kills spiders. You don't need anything spectacular like a spout that shoots ten feet or anything.
Make sure there is little to no wind outside when you are ready to spray. Start at the base of your foundation, hold your hand about a foot away from the cement and spray the perimeter of your house. Make sure to also spray around windows, door ways and under stairs. Spray window wells as well as any cracks in the cement.
Spraying the outside of the house is often enough to keep spiders out but if you have an especially bad spider problem you can spray inside as well. First remove all people and pets from your house. Open your windows to get some air circulation as you should not be breathing the spray at all. You may even want to wear a mask if you think it's going to be a problem. Spray the floor boards and around every door and window. Wait until the spray is dry and the room is aired out before letting everyone back in the house.
How often do you Spray?
You're going to want to repeat this process about every 3 months. To make this effective make sure you are spraying hard to reach areas. Don't skip any areas or coat them lightly. If you want to spray like a professional then you have to make sure you do a complete job.
Control Spiders without Spray
Look at the spiders that are at your house. If you have a lot of jumping spiders, you don't need to spray at all. Jumping spiders eat the other spiders and are no threat to you. Think about the spiders that you've seen in your house. If you only see jumping spiders then the situation is already under control. Don't kill the jumping spiders. Either relocate them outside if you can't stand them inside or just cohabitate with them. If you kill them you will notice other, perhaps dangerous spiders, will start to show up.