Clean Up - Ants love to take advantage of spills, crumbs, garbage, and pretty much any mess that humans create. So the best way to keep ants away from your house is to practice cleanliness and avoid attracting them in the first place!
Use Ant Repellents - Another way to get rid of ants is to drive them away. (See the notes section below for options!)
Check Indoor Plants - Look for ant hills, disturbed dirt, or actual ants moving to and from the plant. Infested house plants will die, so it's best to just dispose of it. If you re-pot, you may preserve the queen. If this is a big problem at your home, try citrus rinds around the rim. Lemon or orange works great! Small organic farmers often use this trick to keep pests off their plants.
Keep Up On Yard Work - When yard debris isn't addressed, or plants grow right up to the outer wall of your home, ants consider it a permanent living space and make their home there. So cut back the ivy and other vines. Move landscaping a foot or so away from your home.
Cut Off Their Food Source - Make sure you have no sources of food just sitting there inviting ants inside. Check the cabinets and under counters. Make sure containers are clean and tightly sealed. The pet food and pet bowl can also attract ants, so check them as well.