How to make silicone molds for sculpture crafts？

How to make silicone molds for sculpture crafts:
 
1. Use a plastic bowl to hold 500g of silicone rubber, add 1.5% of curing agent at room temperature, mix thoroughly and set aside.
 
2. Lubricate the master mold blank of the model product with release agent.
 
3. Surround the lubricated mother blank with wooden strips. The wooden strips are also treated with release agent. The space in the middle is preferably 2-4cm.
 
4. Slowly pour the prepared liquid mold glue for handicrafts along a fixed pouring point, and shake it from time to time to clear the air inside.
 
5. After the silicone glue has completely cured for 60 minutes, surround it with wooden strips, leaving a 4cm gap and remove the original wooden strips.
 
6. Mix 1000g of gypsum powder with water and pour it into the wooden frame, filling intermittently (the wooden frame is divided into two parts using plastic sheets to facilitate mold removal).
 
7. After 20 minutes, lift the wooden strips and the silicone mold is completed.