Look man, avoid roses, chocolate and candlelit dinners like the plague. This is the REAL world, and the only people that do that are the ones that read it in a book and can't think of anything better and less cliched. The key is to be personalised. When getting her presents, get her something that she'll appreciate but nobody else will understand. THAT is special.
For example- my girlfriend and I met at a foam party, which is basically a one off nightclub event where they shoot foam and suds over the crowd as they dance the night away (and yes it IS awesome). We started dating not long after and as her birthday was around the corner, I decided to get her 3 things:
First, she didn't have a DVD copy of her favourite movie, so that one was a cinch. By itself it'd be pathetic though (and she later said she had guessed she'd be getting that anyway)
Secondly I knew her favourite music was Radiohead, and instead of getting her an album that I figured she'd almost certainly already have, I decided to get her something with a twist- there's this band that converts entire rock albums to reggae, and OK Computer was one of them. Even if you're not into reggae, it's different, and a novel twist on something familiar.
BUT EVEN THAT ISN'T ENOUGH, so for the third part, I looked up places that sell special kinds of soap. I went down to a store one day and went through the shop asking employees and scouting out the one that smelled the nicest. I got a respectable sized chunk, wrapped it up, and attached a little note to it that simply said
"Because you can never have too much foam

"
And you know what? the next time I was over at her place, there was that little note, blu-tacked to her bookcase where she could see it every day.
The key to a girl's heart is exclusivity. Nobody would have understood that soap present but her. Also it was different, and showed I'd gone out of my way to get something special. In-jokes are the way to cement a relationship with a girl that nobody else has. Always be thoughtful, different, and special to her.
The End.