Please guys...no more 'teenage anxiety' problems here, we all get them, it's flipping puberty - just watch the Eddie Izzard joke on puberty - that'll explain everything to you.
Because I can sympathesise, I'll say what I can, you're nervous because you scared of making a fool out of yourself - but what results in making a fool of yourself...not much, you just get her in a quiet moment...
It isn't that easy is it? Of course it bloody isn't, you're a teenager, your hormones are freaking off the plot - basically, clear your mind, force your self by marching and keep one and only one focus and approach her with what you want only in your head. If other thoughts occur, get rid of them by coming to the conclusion that'll she'll say yes.
If she says no, big freaking deal, I mean the girl you like needs to like you back.
Of course you'd be taking advice from a person who never actually did it and because of the nerves turned into a complete idiot and peed her off once too many.
But just as a warning, if I see another 'Girlfriend' thread, I'm setting my Bees on everyone - this isn't the place for it, just think this is a geek forum, geeks have the worst experience with girls when they're teenagers.
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Take my attitude towards it there, then give back to me, say 1 1/2 years into the past and give it back
You say you asked them on MSN - not very romantic, actually it's the easy way out to asking my friend, but it isn't exactly an appealing asking out - you chat them up in person, get her smiling and happy then onto the asking out. The smiling and happy is the easy bit, especially if you're compatible - it just takes more confidence to get over the last bit.
The Rabi