I recommend you to read the book Mathematical Modeling written by Xie Jinxing. After eating a book, you have mastered the basic methods of various questions. When you do a problem, you should first look carefully. Then, sometimes you will find that if all the conditions are used, you may not be able to do anything at all. Therefore, you should learn to refine the conditions. Another is to find useful modeling methods from other people's literature through the collection of various materials on the Internet. If you want to get particularly good grades, you must have your own ideas. Modeling in the United States is still very different from that in China, with different difficulties and requirements. At least one person must be proficient in matlab programming. The paper must be written well, with fluent sentences and no typos. Finally, I wish you good grades.