There's an old saying, "Love is friendship, set on fire." In my experience, a relationship that isn't founded in friendship is neither worth being in, nor likely to last. First, be her friend. Then flirt a bit. If she flirts back, flirt a bit more. If she doesn't back off and look elsewhere. First and foremost comes friendship, however.
Also, "Jarn" is an asshole. If you plan to take his advice, I recommend stocking up on porn. You're gonna need it.