Here is a link to the Wilton instructions for lilacs.
http://www.wilton.com/technique/Lilac
or
I found these instructions on ehow website but no pictures.
Make a Lilac out of Icing
Step 1 - Put a number 59 decorating tip on your decorator bag.
Step 2 - Fill your bag with buttercream icing.
Step 3 - Push the icing through the tip, and create small petals. You'll need four of them, and they should be somewhat rounded in shape.
Step 4 - Change to a number 32 decorating tip.
Step 5 - Use your number 32 tip to create a base for your lilac.
Step 6 - Make an upside-down longish shell using your number 32 tip. This will be your flower's base.
Step 7 - Put a number 14 tip on your bag and pipe stars.
Step 8 - Set your flowers on the base you created.
Step 9 - Keep piping until you have formed a cluster of lilacs.
I hope this can help you.
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