One might want to preserve such a flower, but the flower is a bit too thick and a bit too moist. And so the dissecting begins.
Then cut off the yellow star looking thing.
You may put those two parts in a flower press.
Flip it over and cut down into the back, removing the thick circle. This takes out extra thickness and moisture.
You can throw away the circle you've pulled out.
Now there is a hole that you can see through in the middle. It will be covered after it's pressed and your re-assemble the flower.
Now you're ready to put all the pieces in a press the way you would any other flower, with the exception being that you should also put some desiccant board in the press with them. I think it pulls extra moisture from the flowers.
After they're all pressed and dried you can glue the three pieces back together again, and you'll have a pressed passionflower.