The second important thing is oral English. I think the definition here is totally different from the oral English in TOEFL test. I remembered the first time I wanted to talk to my roommate when my oral English was so awkward. Then I just pushed myself to speak to everyone I can talk with. Currently, I was the first international student in ATO Gamma phi chapter at University of Oregon in the 120 years history. I cannot imagine I can do that with my speaking skill, but I actually make it. Thus, practice your oral English and be confident in your oral English.
The third important thing is about drug issues in the USA. When you arrive at the States, you must feel so great for everything and want to try something new which is totally illegal in China. However, I need to say when you have the offer from west coast, such as WA, OR and CA, congratulations to you, but you require more attention because the drug is unlimited and taking drugs is legal in those states. For us, international students, we need think about drug issues and keep ourselves from these issues.