Cut the cucumber in half lengthwise and scoop out the inside.
Sprinkle salt on the scooped cucumber and let it sit to draw out moisture.
Cut carrots, imitation crab, pickled radish, ham, and other fillings into thin strips.
Remove excess moisture from the salted cucumber.
Fill the cucumber with the rice and prepared fillings.
Roll tightly using plastic wrap or a bamboo mat.
Cut into bite-sized pieces.