Get beef fat trimmings or suet
Cut the fat into small pieces
Place the fat in a heavy pot or slow cooker
Heat on low until the fat melts
Stir occasionally to prevent sticking
Continue cooking until the solid pieces turn golden and crisp
Strain the liquid fat through a fine mesh strainer or cheesecloth
Pour the strained fat into clean jars or containers
Let it cool and solidify
Store in a cool, dark place or refrigerate