Know big picture or logic of ethics, solve many practice questions (diversify sources of questions but do not forgot about original topic test, eoc questions from curriculum). Ethics is VERY important , not simply it is 15% weight but there is final judgement on exam if you near below MPS.
The more practice questions the better. I recommend read curriculum, not third party review. Special attention to practice problems inside each standart.
On last exam have been very tricky questions, be prepared!