Hello

I have a Language Analysis SAC soon, and I have a few questions on things that I'm not too sure about.
Firstly, do I have to name the technique/device that the writer is using? I know that
just listing out techniques won't get the mark, but to maximise my chances to score as highly as possible, would I have to name the technique being used on top of the intentions and the impact on the audience?
Also, I have a tendency to back track and cross out what I'm writing because I feel like using a different expression, or because I feel like changing my wording would make my essay flow better. This results in practically half my essays consisting of crossed out lines and messy hand writing, not to mention it wastes a lot of time. How can I stop doing this? I've done two practices under times conditions (70 minutes) and I haven't improved.