I am a mechanical engineer full time and an avid investor in my spare time. I once read that the way to be an expert in your chosen profession is to seek out the best in that field and pattern yourself after him. General George Patton read everything he could about Alexander the Great, studied how he fought battles, and eventually Patton won battles just like Alexander the Great. I have chosen to pattern myself after Warren Buffett, and I have spent thousands of hours of deliberate practice adopting his intrinsic value approach to investing. My main circle of competence is in the energy sector, primarily oil and gas producers.