Drinking pool side in Vegas, in July? I love it. Look into a cabana, they cost more than hotel rooms but are awesome. Back in the day (like 15 years ago) you could get a cabana for $150-$200 a day, from about 10AM to 7PM. Big screen TV, ceiling fan, water misters, waitress service, stocked fridge. Stocked with water, juice, candy, fruit, I would take some of that shit out and replace it with beer and mixers. Lay out in the sun or in the cabana, it is the only way to spend a whole day at the pool in July. Unless you get to the pool at 7AM and try to reserve some chairs in the shade, even then the chair reservation thing is dicey at best (depends on the pool rules) and the sun moves so you lose your shade. If we were in Vegas for a week we would do 2 days in a cabana, parts of the other days at the pool. 3 or 4 hours is about all I could take in that heat, and the drinks really cost at the pool. Unless you stock your cabana fridge with your own drinks
Now a days, they give most of the cabanas to high rollers, it's tough for a low roller to even rent one and they are more like $500-$1000, which is crazy unless you have Rush money, oh wait....
If you have a casino host, talk to them, if you have any kind of a comp coming ask, maybe you get lucky and get a weekday. Some places also split half days. It never hurts to ask a host for shit, you never know.
One last suggestion that will get blasted, Golden Nugget downtown. I know DT sucks! But GN is a nice place with a great pool and you can get a cabana there for 300-350 on a weekday. If you really want the full on, all day drinking at the pool, Vegas experience, that is the place.
Unless you are a high roller, in which case you know more about this shit than I do.