I don't always pre-wash it mostly depends on the fabric. Blacks, dark blues, purples and red are the ones that I take the time to prewash. I always pre-wash swap fabrics too. I put yardage evenly around the washer and have yet to have a problem. Stitching the ends would be a good idea that I will now consider to prevent raveling. Great Idea. I usually cut all the raveling off after I was the fabric. I don't routinely put my fabrics in the dryer. I hang them to dry. Then I press them. Every one has a slightly different way to pre-wash the end results are what matter.