You know going in that there won't be any chlorine or CYA in the water. So as soon as the pump is on and the water is circulating and you've found no leaks, add chlorine to get to 3 ppm FC. Then you can fuss with the CYA granules and get them in the sock(s) and resting in the skimmer (Don't block all the flow) or dangling in front of the return so it will get pummeled by the water. Then you can test pH and TA and CH. If pH needs adjusting, use poolmath to figure it out. The CH is just a point of interest; low doesn;t matter and high isn;t going to be improved any by draining and refilling since it's just been filled.
At that point, the kids can get in.
Maintain it using bleach and acid as needed while the CYA dissolves. As the CYA dissolves, guesstimate how much is in there based on how much is left undissolved and what you targeted, and adjust the daily FC level off that. Remember at the moment it's a bleach pool.
Salt can go in any time, but it's more fun to dump the crystals in when the kids are swimming. It will need at least 24 hours to dissolve and mix. Assuming the CYA is also dissolved, you just flip on the SWG and let it take over the chlorinating duties.