Both my I 140, one based on national interest waive (NIW) and another one based on EB1 Extraordinary Ability (EA), have been approved within a month. However, I have to say if I have prepared earlier, life would be much easier. Here is a list of suggestions I would provide for others who is in their early stage of preparing NIW and EB1.
1. Work hard and get more publications, rewards, medium reports, and patents. These are hardware for NIW and EB1 applications. However, if you are a little bit weak at the point when you start to submit your permanent resident application, you can still make it. When I submit my application, I only have 1 published journal paper (in my native language), 2 accept journal papers, one patent. No reward, no citation, no medium report.
2. Try to review as much paper as possible. You will see the importance of reviewing paper after you read the requirements of NIW and EB1. This made you meet at least one requirement: judge others work. Furthermore, the one who asks you to review can also provide a reference letter for you in the future.
3. Try to joint at least one honor society that requires extraordinary achievement, such as Sigma Xi, etc. It is easy, but takes time. For me, it took me three months.
4. Attend more conferences and know more people. This is important for your reference letters and network.
5. Try to help others. Help others is the source of happiness. But you never know it will help you in long run. I have received emails from students or researcher asking me about my work. I always explain it with them patiently. These emails become importance evidence of my impact in my fields.
6. Keep all you emails and communications with your coworkers.