How do you tell if a girl is open to being asked out?

I have never asked a girl out, and i don't know if there is any etiquette I am suppose to follow, I'm not afraid of rejection, I'm afraid of rejection because I didn't follow the rules, i just don't want to be in a situation like that guy was in Love Potion No. 9, I think that would really hurt my feelings and I would start crying or lashing out, and i don't want to be that guy.

We need: age, any things the girl does that leads you to swing one way or the other, etc

I mean at the end of the day, just give it a try, make it something casual like going to a movie or getting coffee or going to the park or something. And try and view it in your mind as casual, not SRS dating business. It should become reasonably clear if you've got something going on.

EDIT: In fairness, maybe you shouldn't listen to me, because I don't quite understand the american concept of dating. Like in those sitcoms where a guy would go out with a girl, and the guy would be all "LOL wtf I thought this was a date?" *canned studio laughter* and the girl would go "lolz no way". WTF is the difference?

I don't see the difference either, which is one of the reasons I feel so out of place in these situations, it's like everyone has this code of conduct and no one sent me the memo.

Let me tell you about rejection. It came in the form of cops for me tonight.

I was at the bank putting in my paycheck. The teller (I've seen her for the last 3 months, not too shabby) tells me she's going on her lunch after me. Tells ME, not her coworker. So whatever, I go outside, make a phone call, and as I'm leaving, she's in her car, and says hello, blah blah blah, mentions quite obviously she's working till 2000. Now I'm fucking tired as fuck from a hard day's work, but whatever, I figure I'll drop by at 2000 and see if she wants some chinese.

Needless to say, I drop by at 2000ish, and cops were called because two young guys were parked in front of a bank, in a PARKING LOT FFS, listening to music.

The night ended with chinese food, and now I'm getting drunk.

And I still need a date for tomorrow!!!

what the fuck ryko, you're in canada. what is this 2000 business.

oh and OP: if it pans out, don't make her your princess.

There really aren't any rules...

Age would help.