You cannot make someone love you. There are certain subjects that qualify to people in love that are very close to friendships.
1. Talk with her constantly. To be in love with someone it is advised for you to be honest with each other and try to talk everyday. How was work? What is for dinner? How do you prepare it? What do you listen to while driving in the car? Find things in common you both enjoy.
2. Remain close to her. Not suck together like glue close, but a different kind of close. Pet her head every once in a while. Rub her leg, arm, back, shoulder. Let her know that you are there. Kiss her head, shoulder, back, leg, everywhere. Let her know she is loved.
3. Do the little things. If you live with her do these. Cook breakfast, make dinner, do the laundry, make the bed, set the table, vaccum the apartment/house, etc.
4. Give her gifts. Roses are nice. But know her favorite flowers. Think of jewelry. Women like gold. However, since this is so costly, you might want to look into pearls.