Place bones, vegetables, herbs, salt, and pepper into a crockpot, or a big pot. Pour in water and apple cider vinegar or lemon juice.
Allow the ingredients to simmer for about 24 hours, or for a minimum of 12 hours (simmer longer for beef or pork bones, less for chicken or smaller bones).
Remove and discard the bones, strain out the vegetables, pour the broth into glass mason jars, allow to cool and then refrigerate.
Use or drink the broth within a few days or freeze bone broth in mason jars (just be sure you have left an inch of space at the top of the jar for the broth to expand as it freezes).