Earlier this year I picked up my knitting needles again for the first time since I was a child. I started to knit a cardigan using a pattern (cardigan 1371) by onion.dk. It all went swimmingly until I started on the ribbing for the sleeves. I started over 3 times and could not get it right.
On the other parts of the cardigan the number of stitches could be divided by 4 so I just knit 2, purl 2 on every row. The sleeves however have 62 stitches so the number of stitches is dividable by 4 +2. To get this rib stitch right every other row should be knit 2, purl 2 across the row and every other purl 2, knit 2 across the row. Clearly an experienced knitter would see which stitch to use and would of course know that if the row begins and ends with knit two, the next row should begin with purl 2, otherwise you would not get a rib stitch.