Preserve a butterfly specimen by relaxing, pinning and drying the specimen. Relaxing and drying are necessary to prevent the specimen from breaking or molding in the future.
Collect butterflies for preservation by locating dead specimens or humanely killing live specimens. If using humane euthanasia, lightly pinch the thorax between thumb and finger. This quickly stuns and kills the butterfly and prevents damage to the specimen. To avoid the relaxing step of the preservation process, put the specimen in an envelope, and place it in the freezer until the time comes to mount it.
When working with a specimen that is already dry, relaxing is necessary to prevent it from becoming brittle and breaking. Simply place the specimen in a glass or plastic container with a moist paper towel and antiseptic. Antiseptic products prevent mold growth and are made specifically for the purpose of specimen preservation, but household disinfectants work as well. Relax a small specimen for two days and a large specimen for up to a week.
When the specimen is ready for pinning, push an insect pin through the thorax and between the wings, and secure the pin to a mounting board. Fold the wings down with strips of paper, and pin the paper to the mounting board. Take care not to touch the wings as this damages the colorful wing scales. Place the specimen in a cool, dry place, and allow it to dry for up to a week. Once it is dry, the specimen is ready for display in a shadow box or dome display.