Thanks! In this case I guess you could say I started out with a design idea in mind first. I wanted a tool that could model my whole life in a single view and re-render changes immediately to encourage quick experimentation. I had an approximate vision in my head for how this would look from the beginning, and once I had a decent MVP together, I spent a lot of time user testing with friends and iterating on various design elements (and the onboarding flow) until most new people found it pretty intuitive.