Instead of lighting a candle you could pour sand in a glass picture frame. You could put one of your engagement photo's and have something engraved onto the frame. Have your favorite color and your soon to be husbands favorite color and poor them together into the frame. This is another great idea for couples who are remarrying and have children from previous marriages. Have each person take a color and one at a time poor them into the frame.
Another great idea is to plant a tree during the ceremony. You could set some dirt aside, water and have some shovels. Your guests can watch you and your husband plant a tree together. Later you and your husband can plant the tree at your home together. This is a great reminder of your wedding day that you can see every day.