New to SWG

Start by ignoring that you have a SWG first. Balance your water at a CYA of 40 then once stable (probably only a few days) raise your CYA to 70ish and start SWG. Do this by adding CYA to get to 40 and liquid chlorine. Then test often and maintain adequate FC. Testing will reveal if you need to do anything else to your water, i.e. TA, CH, etc.

This wasn't officially blessed, but should be a good start. Since your water is new out of the tap you can assume a starting CYA and Salt of zero. TFP SWG Startup Guide

Good luck!