If you are making four or more servings, you may want to make them in two batches. It's possible to make it all at once (I did it), but it will overcrowd the wok, and each step will take longer.
Heat the oil in the wok over high heat for about 1 minute.
Add garlic and stir-fry for a few seconds until it turns golden. Careful not to burn it!
Add the chicken and keep stirring until it's no longer pink on the outside (but still raw inside).
Throw in the bowl of cabbage, carrot, and white scallions parts. Stir-fry until the cabbage has wilted and considerably reduced in volume.
Add the noodles and sauce, stirring constantly.
The sauce is supposed to coat everything at this stage. If it starts looking too dry, add as much of the water as desired.
Stir for another minute or two, then add the bean sprouts and green parts of scallions.
Toss for around a minute and remove from the heat.
Distribute to bowls or plates and serve immediately.