Look at each scene and try to find a way to incorporate description. I once used the aroma of baking chocolate cookies to bring the heroine's memories to a happier time and to lead her to a new time in her life. During the scene, the character or characters can come to a realization about her life and how things have changed and need to change. Scents are particularly evocation of memories.
Having one of the characters have to use a sense during a scene can make the scene come alive. Imagine the character trapped in a dark cave or a dungeon with no lights. Try the sense of touch to bring the scene to vivid like. What is the slimy thing she or he feels on the wall. What does the feel of water mean? Can she or he find the exit jsut by touch?
One thing to remember when using descriptive passages, less is more. Finding just the right word to evoke an image of what the reader should experience is great. One word can create a picture that's clear where long strings of words may muddy the scene or lose the reader on the way to the meaning of the passage. Precision counts when choosing the right word. Think of someone's face when they're angry. Beet red, may do the trick. Face flamed. Things like this make the picture clear.