Your fragrance should be such that it lingers on him when you walk past him or hug him goodbye.Guys love good perfumes especially when it concerns the girl they are interested in .Try different perfumes and pick one which best suits your personality.Spray the perfume on your wrists,behind ears and around neck .Also a quick spray in the air will ensure that you leave your fragrance even after you are gone .Just remember not to rub hands because it kills the fragrance.