Instructions

1. Snip off the edge of a piping bag or pastry bag using a pair of scissors.

2. Insert your star tip directly into the end of the bag. If you're using a metal tip, you need to first slide a plastic coupler into the end of the bag, then set the metal tip on the outside of the bag, directly on top of the coupler. Screw the outside of the coupler over the metal tip. Plastic tips often don't need a coupler.

3. Set the pastry bag inside a measuring cup or a tall glass. Fold the edges of the bag over the sides. Using a spatula, gently fold the frosting into the pastry bag. The measuring cup holds the bag in place and makes it easier to fill without getting frosting everywhere. Stop when the bag is two thirds full, to prevent frosting from falling out the end.

4. Remove the bag from the measuring cup and tie off the end of the bag with a bag clip. A twist tie will work if you don't have a bag clip. This keeps the frosting inside the bag and you won't have to hold the end of the bag closed to work out any air bubbles.

5. Place a cupcake on the table, the counter or another flat surface. Hold the piping bag in one hand, with your hand at the end of the bag. Guide the bag around the cupcake with your other hand, which gives you more control over the amount of frosting coming out.

6. Touch the tip of the piping bag on the outside edge of the cupcake and start squeezing gently. Move the piping bag around with your left hand (or right hand if you are left-handed) while using the same amount of pressure. Keep moving in a circular motion toward the center of the cupcake. When you reach the center, pull upward and release the pressure on the bag. Repeat on all the other cupcakes.