Ants leave a scented trail that other ants follow. This allows them to get to and from their homes without getting lost while carrying their heavy loads. Determine where the ant trail begins and sprinkle cornstarch along their pathway. Be sure to sprinkle it in the pathway so they pick up the corn starch and carry it home with them. Leave for 24 hours and allow the ants to carry the cornstarch back. Next, get the ants wet. The water reacts with the cornstarch and creates a cement like mixture that traps and kills the pests. Rinse away after all of the ants have been killed! NOTE: this may take a few hours to be fully effective. But be patient and you will notice a difference. This works both indoors and outdoors!