Fill a container with water and let it sit out overnight to evaporate any chlorine and become room temperature. A small, clear jar works well. You can easily see if the ivy is rooting and know when to change the water.
Water the ivy the day before the cutting. The next morning cut off 6 inches of new growth with at least three or four sets of leaves.
Pinch off the bottom two set of leaves and place the cutting in the container of water. Only the bottom of the stem without the leaves should be in the water.
Place the ivy cutting in a warm area out of direct sunlight. Replenish the water when necessary and change it if it becomes foul. Use water that sat out overnight. In about four to six weeks, the ivy cutting should have plenty of roots and be ready to plant.