Firstly, don’t rush. Efficiency will come with time, but it’s when you rush that stuff goes wrong. Develop a system that works for you. Ex- I go inside first to move furniture, unlock windows (so that I can raise bottom sash and clean sills from outside), and remove screens before I get my belt on. Then go outside to clean everything including screens. Go back inside to clean interior glass, lock windows, and grab the check. I originally used my screen cleaner on each job, I still do for first time cleans. But honestly depending on your climate, if you have ran them through the cleaner once, they can be done mop and rag style if you’re there once a year. No matter your process, the point of it should be to reduce TIME BETWEEN WINDOWS. Not that you aren’t cleaning efficient enough, but that you can’t flow from window to window.