Flies know the way into your house. They also know the same way out. What I do is swat about six flies; not hard, just hard enough to kill them without causing too much bodily damage. Then pull six strands of hair from your head and tie an end around the fly's neck, which is not as hard as it sounds; you'll just need a magnifying glass. The longer the hair, the easier it will be. But if you have short hair, you'll have to make do with that because you cannot--and I can't stress this enough--knock on your neighbor lady's door and ask her for six strands of her long hair. Apparently, that's a bozo no no. She will
call her husband to the door, and he will
tell you to get the **** off their property. You can ask for a cup of sugar or coffee, or even to borrow their lawn mower, but not strands of hair. It's not like I was asking her for six pubic hairs. Ohhhh, wait a minute. She probably mistakenly thought I meant six pubic hairs. I've got to go back over and let them know that I meant six strands of hair from her head. That should straighten this mess out.
So, back to the task at hand. When you've finished tying the ends of your hairs around the necks of the flies, hang the flies around your living room. When other flies enter your house, they'll see the hanging flies, and they will go back the way they came. Works every time. But you have to change flies every two days or they begin to decay and will actually draw flies in because . . . well, they're flies.