at the end of the section, "Shape back:" it says "...ending with a purl row" then in "Shape Crotch:...Purl 1 row"
as for the casting on, just cast on 5 more stitches onto exsisting row then knit across?
sorry if i seem dense! i got so excited about these pants and i'm just not experienced with anything other than flat projects
thanks so much for the help!!!!!!