You'll need a dozer to go down about a foot, and a place for the dirt you remove. Then you'll need a dump truck of gravel, and you'll need some wood for forms. Then a concrete truck with the concrete, and some rebar, of course. Get some floats to smooth it, and some big boots too, and don't wear anything decent.......

And good luck pouring the whole thing without labor to float it.

So, yeah, not exactly DIY for a pad that big, and it's not 'easy' work either.