Steve wrote:
Does anybody have any experience of laying slabs like these? Any advice
or tips to help me survive this job would be very welcome.

As others have said, damned hard work. But I'd also add that you should
consider the real risk of permanantly damaging yourself - if you burst a
spinal disc or something, it will simply never be the same again.
Hernias are very easily acquired, too. What I'm trying to say is, if
you can possibly afford to outsource some d-i-y to a professional (who
will be well used to the work), then this is the job to choose!

David