Don't tell her how you feel without first seeing if she's at least interested in going out on a real date with you instead of just hanging around doing nothing with her.
During your date attempt to hold her hand and if she doesn't let you then it means that she doesn't see you in a romantic light. That is when you should do the fade on her or you can tell her that you want to be more then a friend to her and it will be too hard to keep up the friendship if she isn't on the same page so you'll be going no contact at least until you can get your feeling under raps.
Don't confess feelings for someone who hasn't shown you that she at least has some of the same types of feeling for you. You'll be opening yourself up to being permanently friend zoned if you do that.
Google "Ladder Theory" and read up on what happens to guys that act like male girlfriends. Disregard the disrespectful to women tone though because that's just fluff.
“The willingness to accept responsibility for one’s own life is the source from which self-respect springs.” ~Joan Didion