1. Potato
This method works for both white and sweet potatoes. Take some sprouted potatoes and dehydrate them at room temperature. If your potatoes are too big, cut them in 2-3 sections and make sure they all have some sprouts on the surface.
Plant them shallow in a pot or in your garden. Once you notice some roots growing, add another layer of soil. Sweet potatoes should have more sprouts and grow better when planted deeper in the soil.