Sand the fireplace mantel. Wipe away the dust and paint or restain the wood to give it a new look. Paint the mantle all the same color or paint the front edge piece a different color than the top for contrast.
Nail a piece of decorative wood trim underneath the bottom of the mantel. Crown molding is an example of a trim piece that spruces up the mantel.
Install small tiles along the front edge of the mantel if it is flat. Use small, square tiles or long, rectangular tile edge pieces, depending on the height of the edge.
Make the mantel taller by cutting another piece of wood slightly larger than the existing mantle to create a decorative overhang. Screw the new piece of wood on top of the mantel, making sure it is centered.
Install decorative wooden braces underneath the mantel to add detail.