There was interest expressed in the vertical fold line of the giant edging I'm knitting, so here are some closeups:
Top is the right side, bottom is the wrong side. (Duh.) Remember you can click on these to make 'em bigger. Take advantage of my new camera! In a nutshell, you make a column of slipped stitches (every other row/round, in this case on the wrong side, but really either way works) where you want the fold. The yarn needs to be on the BACK of the fold, or the inside of the fold, when you slip it.
When you DO fold it, it will look almost identical to a selvedge edge where you slip the first stitch of every row as you knit back and forth. (Which comes out to every other row.) It's basically the same stitch pattern, but in the middle of a fabric instead of at the edge.
Isn't knitting cool?