To preserve fresh beets, start by washing the beets with cold water and then cutting off the greens, leaving an inch of stem. Next, place the beets in a pot and cover them with cold water. Bring the water to a boil and reduce the heat to simmer until the beets are tender. Once they are cooked, remove from the pot and let them cool. Once they are cool enough to handle, remove the skin and cut into pieces or slices. Place the beet pieces/slices into jars and cover them with vinegar and salt, then seal the jar tightly. These jars can be stored and used for up to a year.