Add candy melts in a microwave-safe bowl and start heating and mixing at 15 second increments.
Continue doing this until chocolate is completely melted.
Now, pour corn syrup and mix until it's just combined. Please do not over-mix since it will start to break down and become very oily.
When it looks like a wet and messy blob, pour it out on a sheet of saran wrap and and flatten it with your hands.
Let it come to room temperature and then, wrap it completely in saran wrap.
Keep it at room temperature overnight.
Your candy clay is ready to be used the next day.
It will be hard and can be easily softened by kneading for a few seconds.The warmth of your hands and fingers will make it soft.
If candy clay is too soft, chill in fridge for a few minutes to make it firm again.
Roll it out on a surface that's been sprinkled with cocoa powder (for brown modeling chocolate) or powdered sugar (for other colors of modeling chocolate).
Cut shapes with cutters and decorate your cakes and cupcakes. Enjoy!