this is how I grow my own sweet potato slips..IMO it is the quickest way to get sweet potato slips started. First get 3-4 of your favorite sweet potatoes. My favorite is Beauregard (90-110 days) so this is what I raise. Sweet potatoes is a tropical plant, so it needs plenty of summer heat. For those with a short summer, Georgia Jet is a good choice.
Ok now the 2nd thing is to get a container of plastic, mine is about 16x10x7 inches deep
drill a 1/2 inch hole in one end about 3 inches from the bottom, purchase a 3ft piece of "Rope Light", usually at Lowes or Home Depot. these lights are waterproof and all connections are outside the plastic container. Next I cover the bottom with a piece of aluminum foil shiney side up, then place the rope light on top of the foil, curl around as pictured. then I put in 4 inches of potting MIX (soiless mix) then I take the sweet potatoes and lay flat and buried 1/2 way in the soil with 1/2 above the soil. moisten the soil with a spray bottle and do this every couple days. Not soaked but moisten. I then hang a light above this about 3-4 inches, plug in the rope light and it will keep the soil temperature about 80-85 degrees constant which is perfect for growing sweet potatoes.
sweet potatoes sprouting in just a few days
after removing the sprouts from the potato, you can either stick them in a glass of water (they will developed more roots or put them in a pan of soil to root to wait until transplanting