I usually tear off about 1/2 yard of the fabric...giving me a straight line to work with....I starch the dry fabric and iron it...I then put selvages together and make sure the fold hangs straight. The only time I wash is if the fabric has been sitting folded for a long time or has something on it that I did not notice before (like a stain.) I mostly steam press or starch my fabric. I find starch makes the cutting easier if the fabric is thin or drapey. If it is a thick fabric, I only steam press but I always use small amounts like 1/2 yard to do my cutting...so much easier to manage.