Using flash cards prepared by another student will give you some benefits but much of the benefit of the flash cards comes from you having to think about the reaction enough to prepare the card. Solve the more challenging problems at the ends of the chapters. The answers to most of these problems will not be obvious to you when you first read the question. Do not give up too quickly. Do not consult the answer book without making a determined effort to solve the problem on your own.
Many people can read an answer and understand it.
Do not be fooled into thinking you can solve problems because you understand the answers when you see them. Write the solutions out on paper. Regular study will pay off better than last minute cramming. You will get much better results by studying an hour each and every day as opposed to several hours once or twice a week. Before exams review your flash cards and problems.