Light candles to offer a subtle nuance. Try different ideas of using candles according to your man's tastes.
Play his favorite music on the stereo or take him out to a live concert.
Make a special meal for him. Cook his favorite dinner or bring him breakfast on a tray.
Send a loving message. Text him a romantic greeting , or leave a poem in his pocket.
Take the opportunity to demonstrate physical affection. Give him a spontaneous hug, or hold his hand while taking a walk.