I do not prewash. I just use the fabric as it comes from the store. There's usually enough body from the sizing that I do not starch. I always wash completed quilts with one or more color catchers. I like the crinkly look.

I always do a colorfast test and find I rarely need to prewash--take a piece of white paper and rub any suspect fabrics very hard--if there's any color on the paper--wash, otherwise you're safe (although I use a color catcher anytime I wash a quilt no matter how often it's been washed). BTW--this color fast test was shared by a LQS owner. since I don't prewash, I save my starching for when I know I'm going to be cutting lots of bias edges. The sizing in the unwashed fabric gives it enough "stiffness".
I agree with PaperPrincess that cotton sateen seems to have more stretch in it--so if yours is that way, a wash and dry ahead of time may shrink it so it's not so stretchy--not a game changer,but do be aware. Can't wait to see!

I do not prewash except for flannel and don't use starch. So far so good. I don't have any allergies or sensitivities to dyes. I do wash all my quilts when they are finished. No special treatment.

Since I don't prewash, I find that lightly starching helps.

Pre-washed, starched and cut. So far, so good!

Watson

I don't wash my fabrics as I find out if the fabric is going to bleed when I put it in my tub of starch. Just had 2 batiks bleed like a stuck pig on me too. Tried the blue Dawn dish soap as someone mentioned for new fabric dyes this will stop the bleeding. It didn't so went to my Bubble Jet Rinse and that seemed to do the trick. Plus after I've pressed it I figure if its going to strink its probably already done it between the starching and pressing.

As to the sateen, yes, it does have a nice sheen to it as well as a nice feel to it. I tend to grab any sateen backing scraps from one of my local fabric stores. Use the scraps in my quilts and the larger pieces for my backing. Nice drape to it.

Ok....I have to chime in here. Made many crayon quilts and used bright colors, blacks and reds in all shades. All the blacks and reds were prewashed, the blacks up to five times before they did not bleed anymore. What a mess this would have been if not prewashing the fabrics. When I started my quilting life, I did not prewash any of my fabric. Two quilt disasters later, I prewash all of my fabric now. Just imagine that red or black bleeding all over the yellow and light blue crayons! Please wash that fabric! Hugs! Love crayon quilts!

No I don't starch normally, but sometimes I do. I don't wash fabric anymore but I test it to see how it bleeds.

I don't prewash anything except flannel. I did find a great recipe here on the board for washing quilts and it has definitely prevented any bleeding on mine. I generally wash my quilts before I give them away. The thread is "Recipe to Keep Colors from Running" from zozee. I took tessagin's suggestion about mixing it in a measuring cup and then adding it to the water (see 2nd page of posting).

I have a question about the cotton sateen. Has anyone experienced the sateen losing it's sheen once washed?