This quick easy trick will keep your house fly free!
Make sure you have a bug killer spray can that says "kills on contact" It can be for just about any type of bug as long as it says those words on the can.
Open your blinds and spray a stripe of the bug killer along the window sill and base of the glass. Be sure to spray all the windows in your house in rooms where you tend to get the most flies.
Close the blinds leaving a small gap so that the flies can get in to the poison. As the flies get attracted to the light and heat of the window they will land on the poison, clean their gross little feet and eat the poison and quickly die.
Reapply every couple of weeks when you start to notice an increase in flies buzzing around and a decrease in the amount you are vacuuming off the floor.