From Jimmy Bean: How To Do Yarn Overs Four Different Ways. Did you know that there are many ways to do a yarn over (YO)? We didn't either, until Terry shared her knowledge of YOs with us. In this instructional video, she shares it with you as well! Find out the various ways to knit a YO depending on whether you are knitting or purling - and the next time you need to YO, you'll be an expert!