you may try to watch youtube videos of ryan higgins especially if you are not so good in writing. he has many tips, do's and dont's and im sure you will learn from him. try to visit eilts-blog.com as well.
I passed my IELTS in October 2015, with 7.5 average (listening 7, writing 6.5, reading 8.5 and speaking 7.5). If you value my advice, I prepared it using Ieltsbuddy.com, takeielts.biritshcouncil.org, and the best to me “ieltsliz.com”- all are free. On "ieltsliz.com" you have excellent tips, they helped me very much.
I found great paper material in our City library for foreign books (if you have smth. like that).
Also, I used mobile app Elevate (it is free, or if you pay 8$/month you have unlimited access).