Don't understand these instructions

I have a pattern for a cap with these instructions; you knit a k1,
p1 ribbing band, then 1st row (WS) *K1, with right hand needle pick up ridge in back of next st, slip it onto right hand needle and k tog with next st and repeat across row. 2nd and 4th rows are knit. the 3rd row is the same as the first except you k 2 to start the row. I do not understand what they mean by (pick up ridge in back of next stitch). The instructions do not name the pattern this is supposed to make. Can anyone help me with this, please.

Welcome to KH. Can you give the name of or even better link to your pattern?
I’ve seen a video showing this, if I can find it and nobody else has helped you solve it I’ll post a link.

It is an old printed pattern from a 1971 Woman’s day and they didn’t give a name to the pattern. It is for a cap.

GG’ll locate a link but meanwhile, here’s a tutorial that shows how to pick up the ridge from the stitch below. Only follow steps 1-3 however. You’re not making an increase. For step 4, you should knit both loops together.

This works for the k1 part when you work row 1 into the k1p1 rib but for the purl sts, it seems that you’ll need to pick up the ridge in front from the stitch below and once you get to row 3, all the sts from the row below will look like purl sts. I’m guessing a bit here because I don’t know what the pattern stitch looks like.

Thanks for the link. That should do it. I can’t find anything.

Thank you for your help.