This is what I learned from this site...starch before you cut your fabric because it helps to make more accurate cuts and helps control bias edges. They also starch the blocks as they go along. I didn't use to starch but I find it helps my accuracy in cutting--I'm a terrible cutter :roll: I use the Stay-Flo liquid starch that comes in the 2 quart bottle from Walmart mixing it with water in a spray bottle. Some use a 50/50 ratio, some more, some less. I have also used the starch in the spray can.
There's also another brand of starch that comes in various aromas, lavender, rose, etc. I forget the name of it but other's on this board swear by it because it doesn't leave the flakes that regular starch uses but it costs more than regular starch.