I never made sauerkrauts myself, however the subject has been discussed here more than a few times. Here is a list of some of the related threads, browse around and hopefully you will find some useful informations!!
I have never made sauerkraut using this method myself, but you will need to add salt to the cabbage. I always use a crock to ferment my kraut, then can it when fermentation is complete. My recipe calls for 6 tablespoons of pickling salt to 10 pounds of shredded cabbage.
I Googled "making sauerkraut" and found this link for making it in jars:
Actually Kenneth, sauerkraut is a two-stage process ... (1) fermenting and then (2) canning. You might want to read this article which gives you all the directions you need.