I'd be open about it. Go slowly and let her guide you a bit... if she's into you enough you'll be fine. Don't try and cover up any "failings" on your part. Virginity isn't an affliction... it doesn't even exist, it's just a meaningless concept! Sex is just sex. Besides, you've had it in past lives, you just don't remember. That's because it isn't THAT important.
It really is pretty damn good though
