Prepare the main ingredients.-Rinse the outer layer of the Napa cabbage in running water. Cut the stem off. Tear the leaves into long shapes (using hands and/or knife). Alternatively you could cut the leaves into 4-5 vertical sections.-Rinse the radish, peel the skin and thinly slice it (Julienned).-Peel the onion skin, rinse then thinly slice it.-Rinse the spring onion and cut each stalk into 3-5 sections.
Put the torn/cut Napa cabbage in a big bowl. Add the salt and the water into the bowl and mix well with the cabbage. Put something heavy on top of the cabbage to assist saltiness getting into the cabbage. (Osmosis process) - I used a big sauce pan and water to put pressure on the cabbage. Leave the cabbage like this for about 1 hour. During this time, mix the cabbage every 20 mins so that salt water gets into the leaves evenly.
After 1 hour, drain the water off. Rinse the cabbage in running water several times and shake off the salt (if any). Tightly squeeze the cabbage to remove the water.
Put the cabbage and other prepared vegetables into a big clean bowl. Add the sauce and mix them well together.