Think about this: there are so many people in this world that could be possibly doing EXACTLY what you're doing right now. Maybe they have your style, maybe they have your dance ability, or your hair styling secrets, or your cooking methods. If we just think BIGGER and work on believing in OURSELVES, we won't be so worried about the possible competition. And when that worry is no longer there, we are much more likely to share our secrets. Believe in yourself, believe that you're the best, and believe that sharing your methods will help others without hurting you.
For example, I know I have a skill for picking out good music and I never had an issue sharing that with others. Heck, I even share my own remixes with others and they don't even know that I mixed those songs on my computer in my own free time. Why do I do that? Can't they steal my entire class? Technically, yes they can. But, guess what? People can steal my playlist, my choreography and they can even duplicate my outfit if they want to, but they're not ME. That's one thing you must hold on to. YOU. A duplicate will never be as sharp as the original and a copycat will always be a few steps behind you. Don't waste your time worrying about what others are doing and keep working on yourself and share your knowledge with others along the way.
Anyway, as promised