First of all understand and remember: you can be as good, interesting, well-mannered, versatile developed person, a role model, but she doesn't know. She does not see you, she will make the first impression on the first your message. So try to get this impression was not erroneous.
Avoid anything that may seem to her brash, tactless, even just being over-familiar. If then over time you become friends, then we can allow some frivolity, and in reasonable limits. In the meantime, try to strictly observe the rules of etiquette and netiquette.
However, avoid standards, templates. As, for example, she can distinguish you from many other men who visit her page? How to highlight you background, if you're sending her the first message, limited to set phrases like "hi! How are you doing?". Don't be surprised or take offense if she will answer you very cautiously or did not answer.
Exactly the same ought not in the first message "open soul", giving a lot of information about yourself, even if you have something to brag about. This will likely produce the opposite effect: the girl thinks you are a talker and a braggart. If she wants then to communicate – the question is purely rhetorical.
So try to observe the "Golden mean". Be polite and together with the original. Let us only the necessary minimum of information, but as to interest, to intrigue the girl.
As soon as will move your correspondence, we compel her confidence that you are sincerely interested in her and her Affairs, Hobbies. Ask probing questions sincerely rejoice in her successes, achievements. Sometimes I can give her a tactful, unobtrusive advice. Do not forget about the praise, the compliments, because any of the fair sex are very important. And then be sure that she will make a good impression on you, and your communication will give you a lot of pleasant moments.