The first step in making a Christmas tree star is to gather your materials. You will need a square or rectangle piece of cardboard, scissors, a pencil, and a ruler. To create a basic star shape, draw two diagonal lines from each corner of the rectangle or square, forming a star shape. Then, cut out the star shape and fold each point along the diagonal line, forming a 3D star. To add decorations to your star, you can paint it, add glitter, or use other craft supplies to make it your own. Hang it on your Christmas tree and enjoy the festive look!