Pour 2 inches of small pebbles or soil into the bottom of the vase. Place the daffodil bulbs on top of the planting medium so the tips point up. Crowd as many bulbs into the vase as possible.
Add more of the planting medium to the pot. Cover the bulbs until the tips alone are showing.
Add water until the water reaches just below the bottom of the bulbs. Put the vase in a cool spot out of direct sunlight that maintains 50 to 60 degrees Fahrenheit until the roots begin to form.
Move the vase to a sunny window. Water whenever the water level begins to drop. The flowers will bloom in two to three weeks, if you plant the bulbs in January. If you plant them earlier in the fall, it may take several weeks.