True wisdom and insight is always free.
Spend more time around people that both challenge and respect you.
There is a method that works. Find it.
Get one big success at an early age. It’ll help build your confidence for bigger things.
Keep people around you that will tell you the truth.
Be organized. Being organized helps you work better, relax and be ready to find and hand in stuff on time. There are plenty of ways to self-organize and it is best that you find the method that works best for you. The key is to be able to find what you need with ease, including the retrieval of information and your notes
Keep a calendar. Choose one that can fit in your folder or binder. In this calendar, write down all your tests and assessments, and if your school has different academic classes on different days, write those down too. Also make notes of study sessions or time you plan to spend doing homework. This keeps you aware of upcoming tests and other events, so you can study and prepare for them properly
Keep your attendance up. Your attendance is important at school. If you don't go to school, your grades will obviously drop fast because you will have gaps in your learning that are difficult to backfill.
Write down notes. Notes will help solidify material in your head and will also serve as important study tools before a test. Be sure to write down everything important that the teacher goes over.
Make sure to answer and/or ask at least one question per class. This will show your teacher that you're actively participating in class. But more than that, it also forces you to pay enough attention to be able to ask/answer questions. As a result, you'll do much better on tests and quizzes.
Listen actively. Don't just ask questions or talk. Learn to listen too. Eighty percent of the questions you find on any test were explained in class.
Study with friends. Reviewing with your friends during free time can help keep you focused.
Ask for clarifications when you don't understand things. Asking for help if you don't "get" what the question is asking is the only way you're going to find out what to do. Pretending you know and making you up as you go will only prolong the agony and can reduce your marks.
Learn from your mistakes. Don't see mistakes as personal flaws; failures are a guidance in how to do better. Pay attention in class when something is being corrected. Mark your work clearly and carefully so that it is useful in preventing other errors in the future.