I just canned 13 pints. I assume you know the basic pressure canning process. The method I used
Cut off tops, leaving roots and 1" of stem.
Wash well, don't bleed as mentioned above.
Cover with boiling water and cook until tender, 15 to 25 minutes. (I sorted by size and boiled the very small ones about 18 minutes, the large ones for the full 25.)
Drain, cool, slip off the skins and trim the ends and roots.
Slice, cube or leave whole as you desire. I sliced mine.
Pack the beets into hot pint or quart jars. I had two different guides. One said to pack them within 1/2" of the top. The other said within 1". I used 3/4".
Add salt if you desire, 1/2 teaspoon to pints and 1 teaspoon to quarts.
Pour in boiling water to within 1/2" or 1" (I used 3/4") of the top. Release the air bubbles. I used a plastic chopstick to run along the sides and poke down into the beets, also packing the beets tighter while I was getting the air out. Correct the water level as it may have dropped. (The guide I used said to use the water you boiled the beets in. I used fresh boiling water instead. I did not trust that I got all the dirt off when I washed them before I boiled them.)
Wipe the top of the jars with a damp cloth.
Put on lids and screw bands.
Process in a pressure canner at 10 pounds, 30 minutes for pints and 35 minutes for quarts. (I corrected for elevation and used 11 pounds.)
Last year we pickled beets pretty much using the process by 4grandbabies. They were very good. Since we had a more this year, we decided to try to can them. I'll be interested to see how they actually turn out.
By the way, I also canned 8 pints of beet greens. Don't discard those greens. They are excellent. My wife prefers the greens to the beets.
Hope this helps