What you'll need:
odorless oil like mineral oil
empty perfume bottle
Collect some flowers that appeal to you. It does not matter what the flower looks like, you're after the smell.
Fill a jar with odorless oil. Make sure the jar you use has a tight fitting lid.
Cut the flowers off of their stems. Quickly put them in the jar of oil you prepared, and close the jar. Try to make them all fall in at the same time.
Open the jar after a few weeks. Pour it into an empty perfume bottle. Spritz on your perfume and you're done!
Adjust the ratio of oil to flowers to make the scent stronger or weaker!