Walmart "Faultless Heavy Spray Starch .97"...I buy 4 cans every time I go. After yrs of not starching I discovered that my seams come out perfect every time no distortion in the fabric. I starch the entire piece of yardage, let it sit for 10 mins. recommended by quilting teachers, so it soaks in and then iron with no iron issues.
Highly stress to starch before cutting yardage because I found it shrinks your fabric...Found that out the hard way when I did a kaleidoscope quilt and starched each piece after I cut...UGH...can lose up to 1/8 to 1/4 off blocks.