You can find a teacher to study the course once before class, so the effect of two classes will be very good. I used to be poor at math, but later I made it up in this way. Preview before class is a very important aspect, which must be done well. Mathematics can't be solved by reading books. When reading, you should do simple examples first, and then do exercises after class. Don't blindly do reference book topics, leave those topics to do after class.

Of course, if you don't want to hire a teacher, there are some online now, some are free, and you can also save those, which also has certain effects.