craftgrrl | In which I appeal to the knitters

Hi all, text only I'm afraid.

I am trying out a pattern that requires me to cast ON 20 stitches and then cast OFF 20 stitches in the middle of a row (to create a tuft).

My knitting skills are a little basic, and my excellent knitting book is in a box somewhere. Can anyone please explain to me in fairly simple terms how I follow these intructions?

(Edit - I had the "on" and "off" backwards.)

Edit 2 - the actual pattern segment that has thrown me:

"K2, cast on 20 sts, cast off 20 sts (to form tuft), *K6, cast on 20 sts, cast off 20 sts, rep from * to last two sts, K2"

After I cast on the first stitch, everything after that is more like yarn wrapped around the needle than an actual stitch. I've never cast on mid-row before, and I know there is a method that I am just unaware of. Google has not been my friend so far.