.....Ok, in a nutshell, you have to eventually use your fingers as well as tongue/lips. Make sure she's wet already and be gentle as a feather at first, lapping up her pussy with long strokes bottom to top/suck on her lips with your lips, basically just explore that sweet poon and experiment. When she starts getting more into it, move your mouth to her clit, which should already be peeking out. Use your fingers to spread the hood open a little and gently suck on the clit and slowly flick it with your tongue. Kiss it, etc. and then start fingering her with your other hand, using the "come hither" motion to stimulate her stomach side sugar wall. You can speed up a bit when she starts grinding her cooch into your face.
Hell it'll sink in after a bit, this shit isn't supposed to get technical, you gotta just be feelin it.