Although there are numerous ways to create homemade tattoo ink, About.com recommends using a non-toxic formula for safety precautions. Mixing wood ashes as a staining component with vodka, which has sterilizing properties, helps prevent infection from occurring. The site's experts also strongly caution against using homemade ink for tattoos, advising individuals to use professional ink instead.
Burn wood thoroughly to create carbon black ashes. The wood must be burned completely to achieve this chemical reaction. Collecting the ash from fully burned fireplace wood will suffice.
Mix a slurry
Pour enough vodka into the ash to form a thin, slurry mixture. Mix the compound in a blender for up to an hour until the desired consistency is reached. Some mixtures are ready within only 15 minutes of blending, while others take longer.
Add more vodka or ash as needed
Pour in more vodka if the ink proves to be too thick, or add additional carbon ash to thicken the liquid if it's too thin. Experiment with the ink until it's the right consistency for use.
Store the ink
Pour any unused ink into an airtight container for later use. Keep the ink away from sunlight to preserve it well.