Everyone has an idea. Inventing isn't the hardest part. It's the people that stick with those ideas that change the world.
When you do have an idea, don't be afraid to share it. It's the exception when someone actually steals it and cultivates it. Get together with like-minded people who can help you polish your ideas and turn them into reality.
Of course, there's really only one way to turn an idea into something meaningful, and it doesn't include shortcuts. It comes down to one word: grit.