I_am_a_Spoon said:
I know this is unsolicited, but I feel compelled to give you a bit of advice, but first let me commend you on your effort. It takes a lot of courage to ask a girl out for a guy, even one who isn't shy. So, Kudos on giving it a go. A few points for the next time you try.
1: A guys number one tool in his arsenal of water testing is the bad joke. Seriously, if you can get a girl to laugh at a stupid joke, she at least has enough interest in your personality to enjoy being around you. This is a key factor in getting a date. If she can't stand being around you, she isn't going out with you.
2: Confidence is key. This is where you stumble and fail a bit. Girls want to know that they guy they are considering going on a date with is confident enough in himself to not either A: Do something totally creepy, or B: not spend the entire time worrying about how they feel. They want a guy who can keep them laughing and having a good time. I am not going to say this is the most important part in obtaining a lasting relationship, as that relies on completely different requirements for each and every girl, but for a first date, it is important (most of the time, I know there are some girls that like the shy guy).
3: Timing. The more time you take to express your interest, the longer she has to consider why you might be a bad idea. You don't want to move too soon, but too late is going to kill your chances. Shortly after you've engaged her and made her laugh and enjoy your company, you need to move in for the kill. Running away to collect your thoughts and coming back just screams lack of confidence.
4: Expressing your interest early in the conversation. Make sure to keep the topic on point. If you are interested in dating this girl, you have to make it known. This is where the shy guy tends to fall into the "Friends Zone" (take not I put it in quotations as I realize this is bad terminology). If you let her start thinking of you as a friend and not something more, that is where she will place you. As a friend. Don't do the passive aggressive thing of being her friend in hopes of getting in her pants, it won't work (unless you are extremely attractive) and it will only succeed in making you look really creepy. So make comments about how pretty she is, or how you like some feature. You don't have to come on strong, just let her know that you are thinking of her that way.
Like I said before I know the advice wasn't asked for, and I won't claim that everything I said holds true in every situation, as every situation is different (just like everyone woman). I do know that these things helped me to get dates in the past, and I am now in a steady strong relationship that is going on 2 years, with an amazing woman that I love.