Just be gentle. Seriously, about 2/3 of guys tend to go WAY too hard without even realizing what they are doing. This is sooo not cool. You're not rooting for vegetables or chewing on beef jerky, lol. I would start at the lighter end of the spectrum, then if she's wanting a bit more hard, she can let you know. If you start out too hard, she may just want to kick you in the jaw. You can see which is more appealing to you.

DO NOT BITE... unless she asks for it specifically. Not even a nibble, or the scrape of one pearly white. Think of this as the counter version of a blow job. Do you want to be 'nibbled', or have some lovely 'scrapage'? Neither do we.