1. 3-4 ref letters. Better draft them yourself beforehand,in which you have to declear your achievements and their importance to USA,what kind of contribution you have made to your field and US society, to emphasize effect of your research on other scientists' projects, ..... anyway ref letters from fedral insititutes, or very famous big scientist will help you a lot. I once got 3 ref letters from different fedaral research units.That really means something, you know.
2. collect citations as many as you can (both chinese and english are okay,please highlights where your paper is cited, the abstract of chinese papers need to be translated). Addtionally, if your conference proceedings or abstracts are cited, show them up. although some websites cover your research achievements, print and highlight them.
3. Do what they ask you to do: a complete up-dated list of your personal published articles, and a list of citations of your work from a respected professional citation service.
4. cover letter. you have to write a new cover letter for the REF. Please write carefully. you have to emphasize your achievements and influence, your qualification for NIW. If possible, please ask 2-3 natives to polish your cover letter to make sure your answers are right on the target. If your boss and colleague or secretary would like to offer their assistance, it will be marvelous. Good luck.