Cut the vine in early spring while the plant is still dormant. Each cutting must have three nodes or buds to increase the chance of successful growth. Make the first cut just below the bottom node and the second cut 1 inch above the top node. Make the top cut a 45-degree angle so you remember which side is up and which side is down.
Put the cutting in a 6-inch pot filled halfway with a loose potting soil. While you hold the cutting upright, add more soil until it reaches the middle node of the vine. Even the soil surface and tamp it lightly to secure the cutting in place. The end with the 45-degree angle must point upright.
Water the soil so it's thoroughly damp, but not soggy.
Set the pot near a window, but out of direct sunlight. Keep the soil moist until rooting occurs, usually between one and two weeks.
Move the potted cutting outdoors once it forms roots. Do not put it in direct sunlight for the first week, as it needs time to adapt to outside conditions. Transplant the cutting in the ground after a week.