It is just as important knowing how not to ask a girl out as it is knowing how to ask her out. In many cases, it won't really matter how you ask a girl out and that's not what will usually make it or break it when it comes to her interest level. However, it is still important to come across as an attractive, confident guy, especially if you are dealing with a woman who you don't know, or don't know very well, and she doesn't have much information to base her opinion of you on, except the way you meet her and ask her out. In these cases, the small things do matter. 

Recently, one guy asked me a very good question, during which he mentioned asking a girl out by saying: "I was wondering, that if you're single, would you like to go out with me?" At first, this looks like an innocent, direct way to ask a girl out, and there is nothing obviously wrong about it. However, looking closer, I can't help but see that it will necessarily take things in the wrong direction. Although, I am aware that some of the most reputable sources of dating advice out there suggest that asking a girl if she is single is a great way to start a conversation, I believe that more often than not, it's not a good way to start a conversation. First, it is way too direct. You might ask "Well, what's wrong with being direct?" Well, if the girl is already interested in you, then there is probably nothing wrong with it. However, in the vast majority of cases, when a guy is asking a girl out, she doesn't know much about him or doesn't know anything about him at all, and as such - she cannot possible be all that interested in going out with him. Thus, in most cases, asking a girl whether she is single out of the blue is going to "corner" her, put pressure on her and make her feel uncomfortable.  

Even more importantly, I always advise guys to avoid asking a girl out by actually using the words "Would you like to go out with me?" Just like I explain in this video on asking a girl out it's best if you don't use the words "out," "date," etc... Also, it's better if you invite a girl out, as opposed to asking her out.  "Would you like to....?" almost invites "no" in a sense. It corners a girl and is likely to put her in an uncomfortable position. On other hand "lets meet this Wednesday evening at 6 o'clock and take a walk together at this park and grab coffee" sounds like a much more appealing and confident way to ask a girl out. You don't even have to explain to the girl whether it's a date or not. You are not telling her that you like her. You are not telling her that you want to go out on a date with her and you don't put any pressure on her whatsoever. Let her wonder - let her hope that it's a date. And if she asks you "Is this going to be a date?" this will be your perfect opportunity to show you sense of humor and confidence by playfully saying: "Oh, no... it's strictly business" while winking at her.  

So, keep the above simple, practical rules of asking a girl out in mind, and they will likely help you to do better when you ask girls out.