Making Methods
The methods you use to start making your design concept into design expressions depends on what your concept is. Look back at your references: what is the nature of the expression you're creating, based on that collection of references? Is it a product? A service? A system? Or is it more complex than that, like a large service that needs multiple products to support it? If you're unsure, review the Designed Things section of the Design Phase Concept Guide, where you'll find explanations of the nature of Products, Services, and Systems.Depending on what you're designing, you can select from the following making methods to generate version 1 of your design expression, or investigate design methods from other sources.
More Design Methods
If you find yourself in need of more design methods, look at the collection of Design Methods from the General Services Administration's 18F.