Some people spray starch. I always seem to have a terrible time with it, overspraying and having my iron too hot so it scorches the starch and makes the iron gunky. So, I came up with the following method for starching yardage that is faster and easier for me.
For very heavy starching (say, background fabrics for machine applique) I stir up a 1:1 solution of Sta-Flo liquid laundry starch and water, lay the fabric out on my kitchen island, and "paint" the starch mixture on with a large wall painting brush. When the fabric is saturated, I toss it in the dryer and then iron with starch. The fabric comes out with the stiffness of cardstock and is completely stable.
For cutting regular quilt pieces, I don't prewash the fabric and get sufficiently accurate cuts that way. If I did prewash, I would use the above method with a 4:1 solution of water to liquid starch (a much lighter starch solution). The fabric won't come out stiff, but will have enough stability for cutting and piecing.
I have used the heavy starch method when cutting bias strips for binding. It worked great! The fabric doesn't wiggle under the cutter and the cut edges don't distort from handling.
A different way to get accurate cuts for piecing is to get an Accquilt Go! or studio die cutter. Expensive, though.