In a medium bowl, toss the carrot and daikon with the salt. Let sit for 15 minutes. The salt will Dra the moisture out of the vegetables, making them crunchier.
Rinse the carrot and daikon twice and squeeze out the excess water with your hands.
Add the sugar and vinegar to the bowl, and toss well. Let sit for at least 1 hour. The pickles can be stored in an airtight container for a few weeks in the refrigerator.