Guys, this Saturday I am going to take my first IELTS test in Kuningan. I have took ielts preparation private course to help me gain my target (target = 7).
Yesterday, I took some kind a IELTS simulation, I got 6.5 for listening, 7 for reading, 5.5 for writing and 6 for speaking.

Any advice on how to improve my mark, especially in writing and speaking.
I asked my teacher, and he said that my writing lacks of sophisticated word (not the one which like an academic writing), and needs more linking words. Somehow, when I write something in English (like now), those sophisticated words do not come out.

Also how to get good mark in speaking ( it will be recorded, and I think if I talk to much, I will make more mistakes. But if I just only talk a little, I lose my mark).
The problem is grammar! --_--

Thanks before.