Elmer's school glue is not a glue as most know, it's a heavy cream starch. I don't measure the ratio. I keep it as thick as it would go through the spray bottle. The thinner spray is best for smaller baste jobs that can be pressed easy. Sometimes I brushed on the thinned thicker glue for larger areas. I notice the batting make a big difference in how well the glue holds. Batting that has a lot of airyness doesn't hold as strong as the more solid type.