How do you know?

I have decided I am clueless, now given that I am of the male persuasion this may not come as a big surprise, at least to the female population. So here it is, there is a girl that I am interested in but I really can not tell if she is interested in me, somehow I just wish there was a sign, you know something easy like if I shake your left hand I am interested, if I shake your right that means I will listen to you mumble for a while but please don't ask me out. Wouldn't that be easy??

Ok maybe not, but really how do you know? maybe that is part of the joy...... ummm maybe not.