One serving is about 1/4 cup.
To peel the beets without a knife, using only your fingers as a tool, apply a mild pressure to the skin of the beet and push to remove the skin. This takes some patience, depending on how many beets you’ve cooked, but you want to avoid cutting the flesh of the beet away with a knife. Once done, slice off what is remaining of the stem and the tail, and cut the beets any way you desire.
To sterilize your jars, wash the jars well in hot, soapy water. Rinse the soap off in hot running water and place the clean jars into a large pot of water. Bring to a boil and allow the jars to sit in the boiling water, fully submerged, for at least 5 minutes. Avoid contact with the inside of the jar and the rim. To sterilize the seals and lids, wash them as you did the jars, and boil water in your kettle. Pour the boiled water into a clean bowl and drop the seals and lids into the water. Be sure the lids and seals and completely submerged.
Once I remove the jars from the boiling water, I usually place them rim side up on a baking sheet and leave them in my oven that is set to 200 degrees. This will keep the jars just warm enough until you're ready to fill them.
Be sure the jars are not touching the bottom of the pot. This might cause the jar to break. I use a circular cooling rack that fits right into the bottom of my pot. (If you have a canning pot with a wire jar rack, then you won’t need to worry about this.)