Stain the wood that lines the lower portion of your walls with a wood stain the color of your choice. Shades like golden honey, cherry and mahogany are all warm shades. Use a waterproof layer of polyurethane top coat to protect the wood.
Match all subsequent wood pieces to this color of stain. For example, the wood of the mirror frame, the wood of the cabinet, the wood on the toilet seat should all be this color.
Select bathroom accessories that match the tile color. For example, if your tile is mint green, select mint green window treatments and a mint green bathmat and towels.
Add decorative accessories in a third color; this color can be whatever you like. For example, bold shades like red or gold often work well. Add a small gold statue or gold framed pictures to the wall, or add a bouquet of red flowers in a red ceramic vase.