Queen Anne's lace does not hold up well in bouquets because the stems wilt and cannot hold up the flowers. Flowers that are used in bouquets are explicitly bred to have strong stems and long-lasting flowers. It would be better to use the domesticated Ammi majus which is a Queen Anne's lace look-alike. It holds up much better in bouquets.
However, if you still want to use Queen Anne's lace in your flower arrangement, you would arrange it the same way as any other cut flower. Harvest the flowers in the morning then immediately place them in water so that the cut does not callous and prevent water from traveling up the stem.
When you are ready to make your arrangement, cut the stems to your preferred length and remove all of the leaves along the part of the stem that will be in the water. The vase should be filled with warm water and a floral preservative.
To prolong your arrangement, change the water and floral preservative every two to three days, re-cutting the stems each time so that the water and floral preservative will continue to flow up the stems.