Here is a simple recipe:
3 pounds daikon radish, peeled and grated
1 tablespoon sea salt
4 tablespoons whey (optional, but it helps speed fermentation. You can get whey by draining good quality, plain yogurt through cheese cloth or a dish towel.)
Place all ingredients in a bowl, mix well and let sit awhile till the juices separate out. Press into a wide mouth quart jar, letting the juice cover the radish mixture. Leave 2" at the top of the jar. Cover tightly and let stand at room temperature for 3 - 7 days before transferring to the fridge.
If you want a spicier mix, add 6 - 8 cloves minced garlic, a sliced onion or some chopped scallions and two tsps. of chili flakes,
I made one jar of plain daikon in thick cubes and some spicy ones, one with fancy crinkle slices and some shredded.