In short you can’t! Technically unless you have a very big image overhaul you shouldn’t need to, so chose your photo wisely!
Make sure your photo is one that you love and feel represents you well, as it will be the image that appears on your e-ticket for any events you book.
So go ahead, snap a clear, front-facing photo with a plain light background, and make sure it's a recent, safe-for-work shot of just you. We want to make sure we can easily recognize you when you attend an event!