The next day, tell her that you feel like a total idiot for the way you approached her. Ask her if you can both pretend that it never happened. She will say "yes." At which point, you need to think fast. This is the part that will determine if you date her, or if you go down in flames.
"Well listen, I am going to the beach to play volleyball with some friends this weekend... if you aren't doing anything, you should come along."
If she shoots you down without hesitating, then don't waste your time. But if she stalls for even a second say, "Common, I really need to make it up to you after that horrible fiasco I put you through the last time I tried to talk to you" at which point she might give you a shot.
If she politely says no, I wouldn't take that as rejection. It might be that she just feels awkward and is very, very, very interested in not feeling awkward anymore.
I almost facepalmed when I read "Well I thought you were cute so I wanted to talk to you."
Please, please, PLEASE never say that to a girl straight up again... at least not the first time you talk to them.
Follow the other peoples' advice. It's basically what I was going to say.
There was a football player at my high school that thought I was cute. We used to check each other out in the halls. I was a volleyball player and the football lockers were just across the hall, so we bumped into each other one day. And I pulled my courage together and said hi to him. But I was literally so nervous I could not remember my name. You have no idea how embarrassed I was. I never tried to talk to him again... I was mortified.
For what it is worth, sexy women get scared too.
You didn't do that badly. In fact, it's really cute. Try to approach women where you have something to say to them. Figure out something you have in common. Tease her about something. Get into a debate about something... arguing together is the best. Don't go in without anywhere for the conversation to go... that's just awkward for everyone.
Hang in there. Soon you'll be in college and you'll find out that beer has this amazing ability to remove women's underwear.
first of all, I commend you for taking that first step, you're moving in a positive direction. Now listen, I wouldn't beat yourself up over this one, but you definitely should not have tried this type of approach with her friend around. The fact that she was there means that your target is going to be nervous and nervous about what her friend is going to think so she is not going to respond to your comments in a true way.
Personally I wouldn't have told her that you found her attractive. You should talk to girls and let the conversations you have convey/sort of leave them wondering whether you like them. They like this uncertainty and tension because it is exciting to them, which makes you an exciting and interesting guy.
From this point on, if you want to keep talking to her, don't compliment her on her looks or anything for that matter. just get to know her better. then she'll wonder "if he likes me why isn't he mentioning anything about it like before?..." and then you will be creating that uncertainty and tension that you need. Good luck!