>>9334573>>9337530This is beautifully illustrated AND explained, but there's an easier way to do this, especially since the top "toe" piece is shorter than the bottom black "toe" piece, so the seams don't line up.
Open the long seam that runs from the arm, around the tip of the toe, and back the other side, starting and ending about and inch or so beyond the toe seam where the color change happens.
On just the top piece, where the fabric's been flipped, undo the seam joining the black piece to the arm top. Flip that piece over so the edges of the fabrics align at the bottom, and the two "right" sides are against each other. Sew the seam with a straight stitch or back stitch.
Open up the now-sewn top arm piece and use a ladder stitch to close the long seam that runs around the tip of the toe, pausing to restuff near the end, and then closing the seam completely.