Find the buttercream recipe by @chelsweets here.
Step 1: Snip the corner off of the bag and place the piping tip of choice inside. Be sure that only 1/3 of the tip is outside of the piping bag.
Step 2: Place the bag into a tall pint glass or jar and fold the top of the bag over the jar so you can easily fill the bag.
Step 3: Add the buttercream to the bag, filling only halfway full.
Step 4: Fold the edges of the bag back up.
Step 5: Gathering the bag in one hand, push down on the frosting with your hand to remove any air bubbles and compact it towards to bottom of the bag.