Prepare sauerkraut by slicing cabbage thinly, mixing it with salt and a few spices and allowing it to stand for 10 minutes. Pack the cabbage mixture in a food-safe plastic container and weight it down. Keep the container in a 65 to 70 degree Fahrenheit location for about six weeks.
Remove the outer leaves and wash about 5 pounds of cabbage. Shred the heads using a sharp knife or mandolin. Keep the shreds very fine. Mix the cabbage with 3 tablespoons of pickling salt. Options for spices include 1 teaspoon of juniper berries and 2 tablespoons of caraway seeds. Once you mix the cabbage, salt and spices, transfer the mixture to the plastic food container.
Place a cover slightly smaller than the size of the container on top of the cabbage, and place a glass jar filled with tap water on the lid to apply pressure to the cabbage. The salt draws liquid from the cabbage to form the pickling brine. This liquid should cover the cabbage within 24 hours.
Check the container every other day for the first two weeks, and skim off any scum that forms on top. Allow the cabbage to ferment for four to six weeks total. Seal the finished sauerkraut in sterilized glass jars and store it in the refrigerator for up to six months.