The directions I use are from the Ball Canning Book and I would recommend buying one if you do not have one. It has the recipes for other ways to can beets as well.
If you are not sure if you are doing it right check out our posts on canning or again buy the Ball Book and read the introduction to canning.
2 to 3 pounds red beets per quart (Salt Optional)
Wash Beets and drain. Leave 2 inches of stem and tap root on. Put in large kettle, cover with water and heat to boiling. Boil till skins slip off easily. Remove skins, trim top and bottom and slice, dice or leave whole if small.
Pack hot beets into hot jars leaving one inch head space. Add 1/2 teaspoon salt to pint jars and 1 teaspoon to quart jars if using salt. Ladle boiling water over beets leaving 1 inch headspace. Remove air bubbles, a plastic knife works well.
Adjust two piece lids just until finger tight.
Process pints 30 minutes and quarts 35 minutes at 10 pounds pressure in a pressure canner starting timing according to the directions with your canner. Let pressure drop on its own. When you remove them, let cool and then check that they all sealed. Any that did not seal can be stored in the refrigerator and used. Remove rings carefully, wash jars and store in a dark cool (not cold) place.