Miss Morgan: Well the first thing I would do, if I was you, is decide if you think she's interested. If you do, then that (in my own humble opinion) makes the decision to do the following a whole lot easier: since she's interested, tell her you don't like that someone else. Better yet, tell her that you like her! It's a great plan. Flawless, in fact.
If you don't want to do that last bit quite yet though, at least make it clear that you aren't interested in the person she thinks you like. If you don't know whether or not SHE is interested, still make this clear. And then you should probably follow that up with asking her to go do something fun. Like, a date. That should probably help you clear up whether or not she likes you. Hope that helps!
RRA: You have to make the girl know you like her...whether it's just telling, buying her something, bringing her on a date, just talking to her all the time or as much as possible...it all depends on the girl.
And if anyone has a question they would like answered (seriously, anyone, please, ask a question!) email it to miss.morgan.blog@gmail.com