Clip off the foliage in the fall when it begins to brown. Leave a few remaining inches so you can easily see where your daffodils are located.
Dig out a clump of daffodils. Daffodils are planted about 6 inches deep but may be a couple inches deeper since they settle over time. Dig down around the daffodil clump, cut under the bulbs and lift them. A garden fork, spade or shovel works well for this job.
Brush the soil around the bulbs so you can see the bulbs clearly.
Pull off the bulbs growing on the sides of the main bulbs. Replant the separated bulbs. Note that the smallest bulbs may not bloom for a couple years.