Presco Marking Whiskers are used for marking:
Blue, Green, Red, White, Yellow, Orange Glo, Pink Glo
Option 1: Insert a 60-penny nail through the circular opening of the metal clip, then hammer the nail into the ground.
Option 2: Hammer a wood stake into the ground. Hold the whisker at the end opposite the metal clip and hammer the metal clip into the top of the wood stake.