Tips on starting a Web Development & Digital Marketing Agency

I want to know the major things that I need to keep in mind regarding starting a Web Development & Digital Marketing Agency. I am a digital marketer myself and have experience in creating websites on WordPress but I am planning to move on to the next step and create something big. As I lack the coding experience and have almost no knowledge about it. Would it be wise to start this business if yes, what should be my do's and dont's?