The best way to say hi to an unknown girl is by being casual. This may be followed by a brief introduction which should be limited so as not to end being harassment.
You would probably say hi back.
impress her but then how do u impress her?
hi how ru
you just say hi. compliment them or something.
Say hi
you say hi and ask her questions
go up to her and say hi, she'll say hi, then say im (instert name here), whats your name? then start as convo...
Say Hi and Tell Her How you Feel
say hi and ask her some questions to get to know her
You can respond by saying hi back and asking how she is doing. Engage in a conversation by showing interest in what she says and being friendly.
You should say hi nicely, then maybe talk to her i noe this 'cuz im a girl :D
go up to her and say hi, she'll say hi, then say im (instert name here), whats your name? then start as convo...