How do I turn a corner for a rectangle?

I saw a CUTE little poncho pattern, and its basically 2 " L" shaped pieces knitted, then sewn together… My question is… once I knit my longest piece of the L… how do I turn the corner and knit the other piece of the L?? do I just bind off of the longest piece, then pick up stitches on the side I want to start off on??

That sounds right - knit a rectangle, bind off, then pick up stitches along the side. Or, if you don’t like picking up stitches, you could knit two long rectangles, then two squares for the short arm of the L’s, and seam them together.