I'll give you some advice. DON'T THINK ABOUT IT, JUST DO IT. Overthinking a new, stressful experience can kill you(figuratively.... and sometimes literally). Overthinking will psych you out, cause you to freeze up, get nervous, and not go through with it. So don't think about when, or where, or how your gonna ask her out. Just do it the moment you see her. Be spontaneous and eccentric and say the first thing that comes to you, with putting any thought into it. Girls like things like that, as far as I know.(why else would ETF have married me?)
Also, Nebbles' plan is brilliant as well.