Koreans traditionally prepared a large batch of kimchi before the weather got too cold, to last them through the winter. Nowadays, because of kimchi refrigerators and the year-round availability of cabbage, it isn't necessary. But it's tradition, so many people still follow it.
We visited my co-teacher Mrs. Lee's house to help her prepare their family's yearly batch. She had taped a large plastic sheet to her living room floor and piled a mound of salted cabbage on it, with two large bowls of red pepper sauce (prepared with red pepper powder, fish sauce, shrimp sauce, shrimp, radishes, white onions, and anchovies) and some gloves. She demonstrated the technique, even correcting her husband ("I am the kimchi expert"), and we dug right in. Mrs. Lee scolded me once for not using enough sauce, and then later, several times, for using too much. She said too much sauce overpowers the taste, and that she may end up hating me when she gets to my batch.
Mr. Lee cleaned off the plastic mat to reuse next year.
Mrs. Lee packed a giant tupperware container for us to take home, and stored the rest in her kimchi refrigerator.
We enjoyed the fruit of our labor with some steamed pork and cabbage pancakes.