This is fairly easy to do and will help keep your front tires from contacting the suspension or body parts while making sharp turns. Keep in mind this does however, reduce your turning radius slightly.
So what do steering stops do? Well, they limit the motion of the outer knuckle. Since the wheel and tire are connected to the outer knuckle, their range of motion will be reduced. There are two steering stops on each knuckle. One for each side. The stops are located next to the brake disc of the front wheels. (see picture) You will note that the bolt has a nut welded to it. This prevents the bolt from losing its factory setting. To get around this, loosen the bolt and nut. They will come off as one. To limit the movement, add a washer behind the nut. This will be equivalent to making the bolt longer. Note that adjusting the passenger side stop will limit the motion of the wheel to the left. This means if you only notice contact when turning right, you will want to adjust the left steering stop and vice versa.