As a long time entrepreneur, I would say the most important aspect of starting something new is planning. I can not emphasize that enough. It is important to understand product lifecycle and how your new idea will be brought to market.
While planning your journey is important, some aspects of your startup growth are going to be hard to predict. In particular whether customers will like your product or service. I strongly believe in lean methodology, which means creating simple prototypes and testing your market over and over again, until you can build enough confidence in demand for what you are doing. Then it's mostly just following the startup path by the book:
- establish an amazing team
- gain and demonstrate traction
- have a solid growth and demonetization plan
- pitch, pitch & pitch (or if funds are available, bootstrap it yourself until you hit the growth ceiling, then pitch)
- don't forget to watch your life balance, very often entrepreneurs get sucked into the work funnel, set time aside for other things in your life or you will burn out quicker than a candle in a wind.