I wish all the best in your study. Based on my experience, the best way of obtaining high score in IELTS that is making your study of IELTS as a preoccupation matter in your life. In details, think about IELTS, read, write, listen, speak, watch, discuss, search and so forth. Such way will help you to build your experience and increase your knowledge.
If you have a specific question, feel free to reply and ask.
Happy study and good luck.