Honor your level of risk tolerance. You need to have some sense that you can handle the challenges you're giving yourself. Some people can tolerate more risk than others. If you bite off too much, you're likely to end up sabotaging yourself. Start small, and build up your risk "muscle." Be honest with yourself about how much you can handle, and don't try to compete with your colleagues who have a higher tolerance. Do what *you* can do, and make peace with that.
~ What would this risk be worth to you even if you fail? Your risk may be an opportunity to explore your creativity, acquire new artistic and personal skills, build credentials and prestige, make new contacts, broaden your horizons and learn a lot. And there's a certain satisfaction in knowing that you went for your dream, whether you achieve it or not. Regret at never trying can be harder to live with than trying and failing. And what you learn may lead to an even bigger dream that you couldn't even see before.