I was a lip biter as i believe the majority of us are. The method i use for exfoliation is to wait until the skin is extremely flaky and comes off easily, take a shower while continualy running my lips under the water. Then i wet a corner of a towel and wipe the already loostened skin off while immediatly afterwards applying the wheatgrass stuff. Then i simply do not let my lips dry enough for the skin to come back. Whenever i feel them drying out i apply wheatgrass, whenever i feel like the skin cells are starting to built up i lightly exfoliate with a wet towel and apply wheatgrass(or if you already have a good moisturizer that works for you try useing that before spending more money). Everytime i take a shower or brush my teeth, or eat something really wet or sticky i exfoliative and moisturize. These are all mandatory for me.
And during the rest of the day i exfoliate whenever i feel i need to. I believe its important to wait till the skin is ready to come off to start this cycle that way the more smooth and flat surface of the lips will be easier to work with. I don't work during the winter season so its not too bad, when i did work it was alot worse, i would literally rub my lips with my sleeve very hard and would not be able to apply moisturizer as i was embaressed because the stuff i used then looked more like a women's lipstick container rather then chapstick... which has me dreading the idea of going back to work because i know there is now way ill be able to maintain them like i do now, they have literlly been fine for 2 or 3 weeks now... up until today because im planning to post pictures.
Also understand that exfoliating could very well from many logical standpoints worsen this condition in the long run. However i'd like to live now, and when i let the skin do its own thing i'm unable to do that.