My experience is take up cigarettes [again]...
then you can sneak a butt while you move the hoses & sprinklers...

The inground irrigation systems are pretty much DYI however this is one
of those projects where I would definitely get a $ from a pro, your time
has to have some value and this will take a lot longer to do than you
think...

Also next fall you will be looking for a compressor to blow out the
lines so that thye don't freeze...

DD