Start by holding the base of the nail between the thumb and forefinger of the hand not holding the decorating bag (for example, a left-handed person will typically hold the flower nail with his or her right hand). Practice rolling the nail outward, away from your wrist.
Place a small dollop of icing on the center of the nail to hold down an icing flower square.
Start piping petals on the side of the nail closest to your fingertips.
As you pipe, you will need to turn the nail to either complete the petal or add more petals. Turn the nail outward, away from your wrist, to keep adding more petals.
Keep rotating until you complete a layer of petals.