Snap them off and root them in a glass of water or directly into potting soil. If rooting in water, make sure to refresh the water every couple of days and pot them up as soon as they shoot roots. The roots will grow out of the leaf nodes below the waterline(remove those leaves).

I cut off the sprouting ends and pot them up like houseplants. With one per 6-inch pot I get 4-6 slips from each pot. On warm days they go outside, and stay indoors when it's cool, in a sunny, south-facing window. Can't plant them out here until late May.

I agree, potting up is the best plan.

it seems like they would grow an awful lot in a month and a half. and take up so much room.. that would be quite a few 6 inch pots......ah well prob will try anyway.. why buy "starts" when I got "sprouts" from my organically grown ones..... Duh me..... thankyall

If the stems get too long, you can cut off 6-inch tips and root them to increase your supply of slips and control the size of the plants. I do grow mine in pots, but a friend over the ridge, where it's warmer, puts his sprouting sweet potatoes in a bucket of damp sand and keeps it in a warm place. He gets really nice slips this way.