Miles has led teams to build design systems for over 10 companies. He recommends starting with one product to establish foundations like design systems, processes, and culture. Then stress-test designs by launching additional products and features. Finally, streamline and optimize the design system. He also suggests being strategic by segmenting customers, prioritizing quick wins, and taking a hybrid approach for more complex needs. Most importantly, Miles emphasizes that the design system represents the company's design culture.