How do you sew part of a Teddy bear's head back on?

To sew part of a teddy bear's head back on, first align the edges of the torn area and pin them together for stability. Use a needle and thread that matches the bear's fabric, and start sewing with small, even stitches, ensuring you're pulling the thread tight but not too tight to avoid puckering. Continue sewing until you've closed the gap completely, then secure the thread with a knot on the inside of the head. Finally, trim any excess thread and gently fluff the area to restore its shape.