Reverse Shaping Question

I was recently helping my SIL interpret a cardigan pattern. When doing the second half of the front, the directions state to “reverse shaping.” I am soooo confused by this concept! I went back to my Stitch n Bitch book and some other resources, but I still don’t understand exactly how this is to work. I imagine this will make more sense to me as I get more experience with making garments and a better understanding of the effects of various shaping methods :??

Generally speaking, it means to do the opposite that you did on the other side, to make the two sides match.
For example, if you decreased by using a k2tog {for a right-leaning dec}, you would use ssk or skp for a left leaning one.
If you were told to cast off or decrease at the end or beginning of a row, you would do it on the opposite side of the other side.
You need to keep in mind that with the RS facing, the beginning of a row is on the seam for one side of the front, and is on the open edge side of the other side of the front. You may want to put the decreases into a list on a piece of paper and cross them off as you do them. Like this:

  1. Cast off 4 sts on armhole edge, dec 1 at centre front
  2. Work even
  3. Cast off 2 sts on armhole edge, dec 1 at centre front.
    etc…
    This way you can keep track of what you need to be doing, regardless if you are on a right side or wrong side row. Sometimes you will need to do the reversed instructions a row later on the second side. Unless you are doing a project with EXTREMELY huge yarn and needles, this one row difference will be impossible to notice in the finished product.

HTH… holler if you need more help!