It looks like you knit the left hand edging first. Then pick up 85 stitches down the straight edge of that. You don't do it with the tail, they're just telling you where the tail should be when you pick up stitches so you do it on the correct side.
After you pick up the 85, it says to pick up stitches where you cast on. I'm honestly not sure how that will work to make the right hand edge.
It would help if there was a picture.