I'm trying to knit a sweater and have questions about the pattern.?

I'm using lion brand child raglan sweater pullover. For the sweater front it states,"when all armhole shaping has been worked and piece measures same length as back, fasten off rem 1 st each side. Do I continue to decrease every other row as before or cont. With the stockinette stitch. After that I'm not sure about the fastening off the remaining 1 stitch. Help!