Character building, before business building. With this mind, one principle that comes to mind is discipline. Not in the punishing sense, but in the following definition:
1. The controlled behavior resulting from such training.
2. Activity that provides mental or physical training.
3. A system of rules of conduct.
When I started (in life in general) I always had a tough time focusing on tasks (my brain was always running a mile a minute) and no matter how hard I tried I always felt like I was failing. The result? I would quite what ever I was doing and move onto something different (in hopes of finding success).
Discipline was not something that came naturally to me. However I was blessed to have had numerous people in my life that taught me the importance of doing something over, and over, and over again (without quit), until it became habit (good habit). Then from those habits, skills were cultivated.
So if you ever find your-self admiring some ones skill or business acumen and wonder how they got there. The answer is simple; time and application. In the most basic sense, there really is no such thing as someone being more talented than you. Only experience (time) + application of that experience.
Discipline, its important and its never too late to start, or apply (its starts with the small stuff).