I have so many friends in their 50s who are waiting for the Great Leap Forward. Still following (extremely successfully) the career they chose when they were 18. Excelling at it. Enjoying it? Not so much. But they're well-remunerated and that's hard to escape from.
As it happens, I have made several great leaps forward, notably to run ski chalets with my husband in my late 30s... and I have never been happier than I was then. Financially it hasn't all been plain sailing, but making those great leaps forward has given me courage, a very broad range of skills and an entrepreneurial mind set which has proved to be invaluable.
If you are still waiting for the Great Leap Forward, ask yourself honestly what's holding you back.
If it's fear, write an honest list of those fears and alongside, write what steps you could take to allay those fears.
Write another list of what you are really (honestly) good at and match that to the ideas you have. Do you have the skills to be successful at your dream? And if the answer's yes, or if you can easily learn those skills, put the plan in place (it might take years) and feel the fear... and do it anyway.
We only get one life. Don't spend it doing what you ought to do, instead of what you want to do. Make the Great Leap Forward.
I have no special skills, nothing that makes it easier to risk it all and take the plunge. I believe that we all have everything we need to make something far bigger than ourselves.