Today I'm going to give you 3 places to find that inspiration, and hopefully give you a starting point that will lead to a wealth of great cake decorating ideas.
If you have a cake decorating business, the most logical place to start for cake decorating ideas is going to be...
Source #1: Your customers! The best place to find inspiration may be right under your nose! Ask your customers what they want, and get as much detail as you can.
They can bring you pictures or email them, list colors, favorite flowers and atmospheres, and more.
The better the information that you get from your customers, the easier your job of coming up with the cake design will be.
Go to your customers first! Source #2: Think "media"! Go to the bookstore and look at magazines and books related to the event that the cake is for.
Is it a wedding? Look at bridal magazines and wedding related books.
Floral books and magazines is another good place for wedding related inspiration.
The internet can be included as "media", and is certainly another great place to look for great ideas for cake designs.
Source #3: Visit your local fabric store! Even if you've never sewn a stitch in your life, you may have good reason to visit the fabric store! There are thousands and thousands of designs covering just about every theme that have all been taken and put on a flat surface (fabric) that can inspire creativity and imagination.
If you find a design you like, purchase sample and take it home with you.
If you do this regularly you'll eventually have a library of fabric design inspirations readily available anytime you need it! Above I've given you three useful places for finding ideas in giving you creativity and decorating your cakes with inspiration.
As always, there are more I could include but hopefully this will give you something to get started with and get your creative juices flowing.