I always pre-wash all my fabrics. Then iron them. Its so
nice having clean, fresh fabric to work with. Betty Lee

I always wash my fabric as soon as I get home from my LQS.
I sew up the ends of the fabric so it doesn't ravel. Wash the fabric through a wash cycle. (Separate colors from the white/light colors.) And use vinegar in the rinse water.
I want to remove any excess dye and chemicals from the fabric.
I dry the fabric in the dryer and iron the fabric before adding to
my stash. This way the fabric is ready for my next project.
By washing my fabric I don't have to worry about formaldhyde outgassing. I store my fabric in metal bins, in the closet of my sewing room, so the fabric can breath and is out of direct sunlight. Welcome to quilting!

I usually just throw it in my laundry basket and then wash it with my lights and/or darks. If it's a red or a blue I go to the sink and test a corner of it to see if it is a "runner".

I learned to always wash them. Although most don't bleed there are those that do, most don't shrink but there are those that do, and batting? Well it IS going to shrink! You can use a color catcher (which is a wise idea), always need a sharp needle and sharp rotary cutters, and don't forget 1/4" seams. Sometimes the shrinkage is in the seams and not in the fabric. Any fabrics bought at second hand shops or at garage sale wash, wash, wash. Hope this helps. Everyone here has great ideas.

I always wash my fabric with soap - need to make sure the chemicals are washed away, as I am allergic to some of them

I always wash my fabric before making a quilt, and I use detergent.

I do perwash...and I put all the fabric together that is going to be in the quilt...I use the color sheets and if it still bleeds......bleed now so it is equal on the fabric. Have not had any problem with this.

I'm getting ready to cut some batiks. I have prewashed all of them. What is the "different process" that you do with them?

I did a test when I first started quilting. Cut some fabric into two squares....same size. Washed and dried one. At the end they where the same size. This was modern fabric. If I am using some of my Mother's fabric from her stash I will wash it. Most of her stuff is vintage.

I have always washed the fabric, even if its for clothing sewing. And always press it so that it keeps the shape. That said my sisters, dont wash?
Who is right I guess we will never know....
but I know mine are washed and will look great when washed again...For Crhistams one year my sister made us all quilts for our beds. I love it and its still on the bed now, but its been washed 4 times now....She told me she doesnt like to see the wrinkles in it after washing? (told her to iron it then, to much work she said) Thats what makes it a quilt i told her......snuggly one to boot....