After death, your collected beetles will stiffen, and it will be difficult to manipulate them into attractive positions. To make them easier to work with, you must use a relaxing process. Begin by boiling water, and use this water to sanitize a glass jar. After the relaxing jar is sanitized, fill the jar with hot, but not quite boiling, water. Place your beetles in this water and soak them for 15 to 45 minutes or until you can manipulate the beetles' legs and wings easily.
Once relaxed, it is time to set your beetle specimens into their final mounting positions. Make sure the legs of your beetles are in a natural, life-like position. Beetles are winged, and you can choose now to display their spread wings or not. If you want to display the wings of your beetles, carefully lift the outer wings out of the way and pull out the inner wings to a flight position. Use pins to hold the beetles' positioning in place, and mount them to a piece of Styrofoam. Let your collection set for up to 48 hours.
For displays containing multiple specimens, the layout of the beetles is an important factor in determining how the final product will look and how educational it will be. One option is to arrange your beetles by size, either starting with the largest first in the upper left-hand corner, or the smallest first. Another way of organizing your collection is by taxonomic relationship, displaying your beetles in order or in groups according to how closely they are related to each other. There are no hard and fast rules for how to organize your collection, so it is up to you to decide on the most attractive way.
After your collection has been set in their display positions and you have planned the organization of your beetles, it's time to mount them for display. Use entomology pins to affix your beetles to the Styrofoam liner of your display box. Many recommend pinning only through the right elytra (outer wing), but this is not necessary. Take care that your beetles are mounted in straight lines for a more professional display. Label your specimens with paper cards mounted underneath each beetle.