Use the reading time they give you to read over the task in hand. Don't rush it and try jump into it. Use the time you have, there is plenty of it, and there is no extra prizes for finishing in half the time.
Follow the task instructions you get given for inspection and testing as it lists the things you must do and can help jog your memory if you forget something.
When you're isolating something with a switching arrangement in it, ensure you check the thing is isolated on all the possible combinations of switching.. you never know how it's been wired!
Be smart when fault finding. Don't spend too long on one as can move on and come back to it once you've worked through the others.
The multi choice is straightforward, you get given the books with all the answers. So use the contents and index pages to find what you need, if it asks for a definition, don't guess, just look it up.
Best of luck!
