What are the most important aspects to focus on in the writing section of the paper?

This will help the student to get the ball rolling in what he needs to focus on for his writing.

Main points to focus on are ticking the flair boxes as I call them.

These include: 

Subjunctive, Opinion words, Si clauses, Links, Fancy vocab, imperative.

Also he needs to focus on having a good structure, snappy introduction and having a suitable register