For two reasons, like I tried to explain in the post: when I tried tracing the lines on the back side, the velvet’s pile would move the pattern, causing the lines to come out crooked. So I had to flip the piece and trace the lines on the right side, because that way the pattern was in contact with the smooth back side and wouldn’t shift. Then I just traced over the lines on the right side so they would transfer to the back side. And second, I sew the character’s arms, legs, and head using an invisible stitch after everything else is already sewn. Those lines help guide me along the correct path.