Gather a master object, mold box, silicone rubber, mixing cups, stir sticks, release agent, and gloves
Clean and dry the master object
Seal porous surfaces if needed
Build a mold box around the master object with space on all sides
Secure the master object in the mold box
Apply release agent if the material requires it
Measure the silicone components according to the manufacturer’s instructions
Mix the silicone thoroughly, scraping the sides and bottom of the container
Pour the silicone slowly into the mold box in a thin stream
Tap or vibrate the mold box to release trapped air
Allow the silicone to cure for the recommended time
Remove the mold box after curing
Carefully remove the master object from the silicone mold
Trim any excess silicone if needed
Wash and dry the finished mold before use
Store the mold flat in a cool, dry place