Anybody can tell me how to pass F4 by doing self study?
There's an ACCA self study guide that should be really helpful. See link below:
If you have the basic know how of law from your previous studies and assumed knowledge you should not have a lot of problem in passing this exam.
If you have not got it, study on conceptual grounds and try to understand the basics first and then gaining applicable knowledge for the paper and practice of exam questions.
This is an interesting and fairly passable paper.
Good luck for your exam