The only way to get better at NCLEX style questions is to do a lot of them. Buy a NCLEX question and answer book(or a few books) that's broken down by subject. I like Lippincott's Q&A
, the questions are harder than most other sources, but I also have both Saunders books, and the Success series for some classes.
If you're making stupid mistakes, slow down, re-read the questions. Ask yourself, 'do I understand with the question is asking?' Make sure you check to see if the question is asked in the negative, ie. 'a need for further teaching' or 'all of the following except'.
What class is this? Something like Nursing Fundamentals? How comfortable are you with therapeutic communication questions? Those mess up a lot of people early on, the key is to address how the patient feels, no matter how stupid the answers would sound in real life.