I prewash all my fabric, even precuts. I soak precuts in the sink in warm water, the spin dry in my salad spinner, (which I bought my salad spinner for my quilting room for this purpose only). On precuts, I dry on a dry towel and I always starch or use best press all the time. The starch or best press has improved my accuracy sooooooo much. This is just me, but it works for me. That is what you should do, is what works for you.