Great question!
Be fun to be with! When two people know each other well, what keeps the passion alive is challenges, change, renewal in the relationship. You have to take risks and move beyond the limits of your comfort zone.
Deep care is great but when harmony is granted and you want to turn on your man, you must be excited about your life and your future. Falling in love is about excitement! Find the roots, the sources of your life's pleasure, the nectar of your senses, wake them up in you and show him that! wake up your sensuality, connect with your desires! they are your emotional fuel!
Flirt outrageously. Be fun to be with!!! Don't mean frivolous all the time but simply enjoy life. Inner freedom is extremely attractive for a guy. Show him you enjoy life deep inside and that your pleasure can't be challenged or destroyed. Be sexy and take care deep care of yourself. Don't worship him like a god, tease him instead.
Be confident and take risks (I don't mean putting your life, health or future in danger). Try simple steps like talking to people more ins social situations. Be active in social situations. Fun! Don't be exclusive with him or clingy. Stay active, open and excited about life beyond the limits of what you share with him.
Enjoy!