Take the extra fragments of a second to make sure you're entered everything correctly into your calculator. It's worth not losing the marks.
Speaking of calculators, make sure you know the ins and outs of how to do everything on your CAS (or the other one, whatever it is), and with efficiency. Like if you're doing practice questions, don't skip calc bits thinking you'll just do them on the real day.
Don't worry about wasting time if you need to quickly draw up a table to work out those word problem things with the constraints and objective functions and stuff (forgot what it was called). The time taken to get a table on paper is less than getting the info muddled up in your head, then having to start the question again when you get lost.
I'm assuming you've got the content covered, so specifically SAC wise, those are the main things I'd worry about
