I've posted this long ago: I fold my fabrics then use Brass safety pins in the salvages Then wash them they won't tangle up and also are not as wrinkled.

I think it's prolonged agitation and overcrowding in the washer and/or dryer that makes a new fabric look 'beat up' when it's washed.

I now overcast the raw edges of fabrics that are to be washed by machine. I used to occasionally have threads come off or tangle up to an inch on each end - depending on the fabric and how it was cut. On expensive fabric, I figure it's worth the few minutes to preserve as much of it as I can.

Of course, this only applies to those of us that choose to wash our fabrics before cutting them.

Let's say I have 2 yards of material. I fold it in half and again in half, then I pin the corners with safety pins. Wash and dry. You might have some tangle thread on the one end, but the fabric will not be tangled.

If you have a serger, you might try serging the cut edges before washing.

I don't prewash at all.

I read/saw this tip somewhere.
Unfold your fabric so that the selvedges are on your right and left.
Fan fold the fabric from the raw end to the other raw end. Try to keep the folds somewhat even.
Safety pin along the folded sides through all thicknesses.
Wash as desired. You will still get strings BUT you won't have such a tangled mess to undo.

I've had good luck with cutting the corners of all the fabric, it seems to help stop raveling threads. For smaller pieces and strips, I would use a mesh bag. Hope this helps.

The fabric is folded in half length wise when you buy it. fold it again. fold the top end and bottom end together and use a straight basting stitch across them. your fabric will not twist and it will reduse the fraying. works for me

I cut a very small rectangle from each corner of the fabric. That stops the threads from raveling and wrapping around each other. Works with yards or fat qtrs.

Wow! The things you learn on here.