It starts with a...
It starts with anything you want it to. It doesn't matter what "it" is, but it's the intention to have "it" that's important.
Don't become immersed in a sea of tail lights following others, take the path less travelled, it'll be way more interesting. Be all you can be. Follow your hopes, dreams and all that you aspire. Have your "it".
If it feels right, then go with it. Let yourself be all that you can - and then take it up a notch on the awesome dial.