I'm making the "easy and top-down" sweater. I'm to a point where the pattern states: "Now is the time to try it on"--slip the stitches to scrap yarn and try it on. My question is, do I cut the yarn from the skein to do this? If not, will my stitches ravel out? I know this sounds simple, but I'm not sure how to do this without losing my stitches. This is my first attempt at knitting a sweater, and, so far, I've not had any problems. I just don't want to make a boo-boo--(I really don't want to take off these stitches like they say, but I know if I don't follow the pattern, I'll be sorry).