To put on a boutonniere, position the flower on the recipient's left lapel roughly 4 to 5 inches below the left shoulder. Push a pin from behind the lapel up through the fabric and into the flower's head.
Reinsert the pin through the lapel fabric so that it ends up behind the lapel. One pin may suffice, but a second pin inserted in a direction opposite to the first pin adds extra security. You also can drive the pins through the flower's stem or through the leaves on the front side of the lapel.
While jacket lapels are the most common sites for adorning with boutonnieres, dress jacket pockets and dress shirts are other options. To pin a boutonniere to a shirt, select the spot, position the boutonniere, and then insert the pin upward through the shirt, taking up about an inch of shirt material. Insert the pin back through the shirt, and position the flower's head or leaves onto the pin. Use an additional pin if a single pin fails to provide sufficient anchoring.
Give the pinned-on boutonniere a gentle tug to confirm its stability. Use straight pins to pin a boutonniere onto clothing. If a pin bends while you are pinning on a boutonniere, discard the pin and use another.