Build a bonfire that is sturdy and will burn a long time. Use dry kindling and thick, long logs. Place the logs and kindling in the center of a circle of large stones to help contain the fire.
Lean the kindling against each other, then lean the tall logs against the kindling. Place several logs next to each other and have several in reserve to keep the fire going. Light the tinder, which should ignite the kindling and eventually spread to the logs. Keep a bucket of water nearby in case you have to put the fire out quickly.
Bring a blanket for the two of you to huddle under if the night air turns colder, especially if you are at the beach.
Bring along a bottle of wine or Champagne and some plastic glasses for you to share by the fire.
Play romantic music from a portable stereo to set the mood. Bring along an acoustic guitar if you know how to play.
Make food that you can share with each other using the fire, such as s'mores, using graham crackers, marshmallows and chocolate candy bars. Pick up a quart of strawberries from the grocery store. Place a small metal pot filled with chocolate near the flames to melt. Dip the strawberries in the chocolate and share bites with each other.