First of all, you should know your own advantages and ability to withstand pressure. Find your advantage and, if possible, use it to the extreme. If you are good at Chinese, you should strive for the first place in every exam, if you are good at mathematics, you should strive for the first place in mathematics, and so on. Having a strong point will make your self-confidence explode and improve your sense of accomplishment in learning.
Secondly, analyze the learning style of each subject. Chinese, mathematics and English need different ways. Chinese and English need strong accumulation, so reading is very important. Mathematics emphasizes logical thinking, which is very important. So plan ahead.
Finally, learning is a long process. Don't rush for success, step by step! You must work hard. But don't worry.
I hope my answer is useful to you!