Ask HN: How does one put together a branding style?

As a programmer, I am often asked by various people around to throw together websites and apps. Now if I were to start my own startup, I'd like to give my app/website a strong branding style. Like google has material design, apple has their design guide and microsoft has metro. What are some good books/blogs about putting together a design language for a given brand? Also how do you take your brand and naturally integrate it on the web, with android's material design and iOS? Any advice is also appreciated.