Once you know the basics, assembling boutonnieres is a quick process. I usually save my cut flower work (corsages and boutonnieres) for the day before the wedding.
Since I generally create bouquets on holders, (even the hand tied look), the flowers have a continual water source and can be created a couple days in advance. Just be sure to keep in a cool place, mist regularly with Finishing Touch and turn the lights out.
Cut flower work generally doesn't have a water source, so you should only do it a day in advance and then keep in a refrigerator if possible.
Place the leather leaf taped fronds behind the top flower, making sure the edge of the frond is about halfway about the top tip of the flower.
See from the back view that the fern is flat and lays completely against the flower backs.
Once you are satisfied that the leaves are where you want them, secure with florist tape.
All the stems should be bound tightly together and not move. or have large gaps between them.
Now you are ready to move on and add another interesting design element using decorative grass to your basic flower boutonniere.