Instructions
Press "Circle" to raise your sword into the air. Light will reflect off the sword in the direction of the colossus.
Follow the beam of light. Initially, the beam will be very large. However, the closer you get to the colossus, the thinner the beam will get.
Continue to follow the beam of light until the colossus is found. Because the colossus is many times the size of your character, you will notice them as you get closer.