While you are the significant other, it doesn't mean you should freeload and take a vacation every time you are at her house. Sure, women claim a diamond is a girl's best friend. I doubt, however, that having a diamond makes her boyfriend better. Spend your money on activities that help you grow and learn about each other. Actually, do as many activities you can do without spending money.
Girls appreciate a guy who can hold a conversation.
Taking a girl to a movie on a first date is one of the worst things you could possibly do. She will also feel the constant presence of your eyes fixated on her, which will probably create paranoia and frequent mirror check-ups. Take her somewhere where you can relax and have time to talk and look each other in the eyes. Probably because you can't look her in the eye whenever you talk to her. While a girl might appreciate that her boyfriend showers her with gifts, I can hardly see the logic which says a girl would take any guy and swear an undying love to him even if he didn't have the skills to be her man.