I don't want to go out with her?

Yeah, what if I just want to make out/fuck with her?

How do I do it? I'm no good at instinctively knowing these things. Please help.

Ask to be friends with benefits.

...Hang out with her, flirt with her, but never agree to have the "label" of dating/couple.

She's gotta want it too, so... odds are low.

Tell her?

Ask?

"Hey, wanna be fuck buddies?"

I was always under the impression that if that's what she wanted, that's the direction in which things would flow.
Maybe I'm wrong?

You are if we are talking about a man.

I've talked to her a few times, and it seems to me that she wouldn't want a relationship from a guy, just making out/sex.

I haven't talked to her well enough to make it flow in that direction yet.

Dont ask. Just rape.

Just man up and ask her to be your fuck buddy. Lead up to it with a few jokes about fuck buddies or something. Mabey she'll bring it up - you never know....

Remain good friends. Continure hanging out, etc. Flirt a little, but not too heavy. Just enough to keep her away from other men...

Then, one night, let things get out of hand, and you two have sex.

The next day, you should be able to pop the question... Although a statement as bold as "Let's be fuckbuddies" might not be the best way to phrase it. Tell her you had fun, and if she had fun too... then why should you two stop.

Just be to sure to make it clear, it's just casual. No attatchments.

(Whether you stay true to that is another matter.)