Drop some knowledge on her
Don't lecture her about where Cupid's arrow originated. We mean show this woman how well you know her. Artisanal chocolates are a great start, but getting macaroons because you know she loves coconut takes your sweet surprise into the clouds. If you bring a bottle of wine, great, but if it's a sauvignon blanc because that's what she always orders at dinner, you're winning.
Real romance comes from listening. Some women hate flowers and consider them a waste of money. If you've been listening, you should know that by now. If you bring her chocolates and she's lactose intolerant, you fucked up. She can tell when you've been listening.
Also, many women are guilty of hint-dropping. Not because she needs everything she mentions, but because she wants to help you. Please, listen to your girl! If she's casually mentioned 300 times that she loves cupcakes from Magnolia, bring her a damn cupcake!