When in use, drop a small amount of white glue into the concave pit on the base, making sure not to spill it. Then, after closing the upper mold, place 5-8mm long model grass powder into the conical hole. Gently shake the mold to allow the grass powder to fall down the hole. Let it sit for a while, and then separate the molds after the glue has dried. Use tools to gently remove the grass from the base cylinder. To prevent the upper and lower molds from separating, you can use masking tape to fix them together.