Aditya’s post “Mantra for Entrepreneurs’ reminds us to just get out there and do it. Forget what the “experts” and well meaning friends tell you, just drill! Do not stop until you find that oil well.
This is so simple it sounds stupid, but it is amazing how few oil people really understand that you only find oil if you drill wells. You may think you're finding it when you're drawing maps and studying logs, but you have to drill. -- John Masters
That's why I said, if you have some idea that you want to start, just drill it. Don't worry about not having related prior experience or competency. Don't worry about the domain knowledge …. There are tons of ways to acquire that knowledge and get started.