mitten knitting

[Cheery]

I have difficulty with knitting the thumb opening of my first mitten. The pattern indicate the following: knit 1 edge st, k1, slip next 13 sts onto a piece of waste yarn, (I'm ok up to here) than cast on 13 sts in pattern, what does that mean. I tried to cast on but it does not look right.

Help anybody.

[Ingrid]

Hmmm. That doesn't sound right. The 13 stitches that are on the waste yarn are the thumb, and at that point a pattern might have you finish the row (or round) in pattern, and then cast on a couple of stitches above where the thumb is.
Where is the pattern from?