How you can make her know that you love her?

You can't make someone love you, but if she is interested in you then just ask her out and let her get to know who you are. NEVER change who you are for the sake of anyone else if you are a good person which I'm sure you are. Just because some girls may not become interested in you doesn't mean there is anything wrong with who you are inside (and that counts!) Ask her out and go some place where there are other people. You could even double-date. Ask a buddy of yours if he'd double-date with you and this girl. It makes it a little less stressful. Don't be overly attentive to her, but be nice, listen to what she has to say and be honest about yourself to her. As you get to know her then buy her the odd bouquet of flowers, perhaps a little bracelet as a memento from you. Just let nature takes its course. When you have been going together for a few months, and only then, tell her how you feel about her. Be independent, be honest and the rest should come quite easily. If one is too nice at first to someone they are going with then one or both partners can certainly take it for granted. Good luck!