While I was watching my pool installers last June, it became apparent to me that getting all the support blocks for the legs perfectly level with each other took much longer than spreading the sand, placing the actual ring, walls and top rail. If you can't do it all in one single day, maybe stop with the blocks placed and sand spread. Then start first thing in the morning with the ring, walls, top rail, etc and then liner install.
I thought one of the coolest things they did was attach a shop vac hose inside the liner so they could remove all the air between liner and walls. That was before I knew that it was pretty standard practice.