It isn't surprising that golden-yellow saffron, the world's costliest spice, is associated with Leo! It's been used in perfumes and cooking for thousands of years.
Alexander the Great healed his battle wounds with saffron-infused water, and the Phoenicians used it to treat melancholy. Try its grassy note in unisex Lady Gaga Fame (from someone who knows something about theatricality).
Also associated with your sign is chamomile, found in Clinique's Aromatic Elixer, Bvlgari's Petits et Mamans (a flowery scent for girls), or Cadillac Black for men.
Add other Leo scents of rosemary, bay, and sunflower via aromatherapy candles and potpourri.