Need Help with term wrap and M1

Pattern reads K 5, sl next st as to purl, yf, sl same st back to left hand needle, turn, K 5, turn, K 5, yf, insert right-hand needle as to knit under wrap and knit tog. I need to know with a picture the under wrap and would I end up with extra stitch because I do when I try it. Also I need to know the same thing for a purl stitch but go into the back. Any help out there would be greatful.

See this video: