I just started knitting again after many years, so I'm a beginner again. I just finished my 2nd hat with this pattern, and after doing a miserable seam on the first one, I should have corrected the pattern, but I didn't. I would like a nicer seam this time. There's plenty of stretch, and I used all 80 cast-on stitches this time to allow for a wider seam. I also slipped the first stitch in each row this time.
I could hide everything and keep my ribbing if I take in 2 stitches on each side, but where would I do my stitching?
Anything on the edge will be hidden because mattress stitch is done on the outside and usually one stitch in. You can do it further in, but it will make a thicker seam. There is a video under the Knitting Tips section.