When do I stop preparing, and start performing?

[David Morad]

I'm a young investor, who has been very interested, passionate even, about investing, and learning about it. I've been reading all I can, and listening to all I can about money, investing, real estate, stocks, and such, and my question is this; when do I stop learning about preparing, and start seriously investing. I know I will never stop learning, and I strive to learn more every day. I also know that it is different for everyone, depending on their situation. I am also in the stage where all of my peers are going away to college, or starting careers, but my passion and interest lies in investing, and they all say that is dumb, and I'm constantly told to not start seriously investing until I know what I am doing, but I also know that there's only so much to learn without actual experience.