Collect hanging frames. If desired, cut pieces of thin plexiglass to fit inside of the frames if you don't want to paint on the glass.
Print out pictures of your favorite leaves to coordinate with the size of the frame. Use painter's tape to tape photo behind plexiglass. Using Hauser Dark Green (or desired color), paint the leaves in.
Remove the taped photo from the back of the plastic. Using various greens and a brown, paint in your shadows and highlights on each leaf.