Lets get started by saying that i have no problem with approaching women I don't know and I think that I'm not too bad at it, but where I really have trouble is asking out girls that I already know. I always get lost in conversation or don't know how to approach them as anything more than a friend, my normal approach of going up to a girl and introducing myself doesn't work because they already know who I am, so what I'd like to know are some tips for approaching an acquaintance in a sexual way and/or how to stop the conversation going into the same boring things we always talk about like school and work. All answers are appreciated.