We have squirrels living in our attic.how do we get rid of them?

They are really starting to move around alot and I think they may be chewing through wires or something,because every now and then our lights will flicker.I'm beginning to worry,Please Help!!!!We have squirrels living in our attic.how do we get rid of them?
Moth crystals or mothballs toss them, sprinkle them , fling them in corners; it should keep the little vermin out of your house. If they are eating your wires, we would melt the moth crystals in an old pan, then paint the liquid while it was still hot near the areas that they love to chew. It works works for mice as well. I also paint castor oil on floor boards along trails where they walk, it gives the little critters an intestinal flush, they learn pretty fast that your house is not the place to hang out.We have squirrels living in our attic.how do we get rid of them?
Call a professional service. When the pests are gone fix the hole they got into the attic through.
moth balls they hate the smell then check for openings and close em