But Seriously...
I am sure it has changed since I went through, but in the early stages in particular, there was lots of emphasis on cleaning and polishing. Since the more stuff you have, the more you need to clean/iron/pollish, the best advice was to have a car/van/estate to keep as much stuff in as possible.
A sleeping bag is useful to avoid messing up your bed. Some of the guys on my flight even elected to sleep on the floor rather than have to remake perfect beds.
Minimise the number of WCs and Showers in use to reduce the amount of cleaning required.
As for the rest of it, sense of humour is the key. Try your hardest and don't let the system grind you down.
Stayed at Cranditz a couple of years ago and was booked in to YHOM. When we got there, found that there was no room in the main mess, so had been put in the Annex .... the Barrack Blocks formerly known as 'No 2 Mess'. It had not changed a bit - tiny beds and that bl@@dy copper pipe under the sink that always needed pollishing. Fair to say that no-one slept very well - I for one had nightmares! Visitors be warned!
STH