A lot of people made the mistake of just doing the engaa papers once.
what I did was I did each paper once, then collated every q I got wrong, and literally did them again and again until I knew completely how to answer the q. (dont do the qs you get right again, obvs this will waste time)
Also as you prob know already the real killer is time, so you should sit every exam in timed conditions, maybe even a little time less just to get you used to the pressure.
A lot of the people I talked to after the exam said they could prob answer the qs reasonably accurately any other day, but in that exam room, with the timer literally dropping in front of you with intense pressure its a completely different story.
So really drill down on time - if you nail this, youre pretty much sorted.
since you have about a month, just focus on doing the engaa papers (some qs again as well) as anything else id say is a waste of time.
and again DRILL ON TIME, focus on finding the fastest way to get the answer, not just any way to get the answer.
good luck