Of course every woman is different. We all like different things, and, it is true that what works wonders one time may fall a bit short the next, that's why paying attention to verbal and non-verbal cues is so important.
Generally I like it to start slow, just like being teased and to slowly work it up, I find that the slow build up of stimulation is mind-blowing.
I also like to be "explored"-meaning that you take the chance to lick and suck all over for a bit before getting to it-again, it has to do with the build up. But at some point, I do actually want you to get to it, starting with flicking and moving to sucking or even VERY light nibbling (I won't even use the term biting because even that is too hard).
And, finally, as I literally can't take it anymore and my body is trembling from over-load, the tipping factor (for me anyway) is to have a couple of fingers inserted slowly. Sometimes I like the twisting method (just as the name suggests) while other times in-and-out is best. At that point my body is so hot and tingly that that one little bit of extra sends me over the edge and literally makes me want to jump all over you.
I do have to agree with one common thing that EVERY girl likes-we want to know that you're enjoying yourself. Whether you make small noises or tell us after or before, it doesn't matter, but in someway showing that you like to makes amateur moves ten times better than super skilled men that seem bored. My guy makes little moans that I find unbelievably sexy.
The only other piece of advice is to pay attention. Girls subconsciously show you what they like by the way that they breathe, move, moan, "Oh god", and wetness. Paying attention to things like that will let you know when you're doing a good job.
P.S. Moaning your name, pulling your hair, and moving her pelvis in tandem with your tongue are VERY good signs.

This was hilarious and the best dan savage column I have ever read