Wash, peel, and cut into matchsticks/julienne carrots and daikon. In a colander over a bowl, toss salt with carrots and daikon, allow to soak for 15 to 20 minutes. Gently rinse and squeeze excess water from vegetables. Add to sterilized jar(s).
Heat sugar, water, and vinegar until sugar is dissolved. Remove from heat and allow to cool.
Pour cooled vinegar mixture over vegetables until completely submerged. Seal jars and allow to ferment on the counter for 2 to 4 days. After the first 24 hours, check the ferment every 12 hours and taste if the sourness is to your liking. Place in refrigerator, it will keep for a couple of weeks.
Ferment will be different for each batch; humidity, heat, and air will play a part. I typically do a 2-day ferment, sometimes 4 during the winter months.