Paint each wall a different color. If you prefer to use the same color throughout your home, opt for different shades to distinguish the difference between each wall. For example, paint your hallway light blue but your living room a deep navy. If you opt for completely different colors, choose shades that complement one another. For example, opt for white and green or red and black. Avoid colors that clash dramatically. If your color scheme is too extreme, it will diminish the collective appearance of your two rooms.
Place an item on each wall that establishes a theme for the room. Choose an item that, if presented alone, states what the room is all about. For example, place a picture of a bowl of apples on a kitchen wall, a clock on an office wall, a picture of your favorite book cover on your library wall or a family portrait on a living room wall.
Add congruity to your walls through similar decor. While it's important that your walls are different enough to establish their unique identities, it's important to add a few similar elements to present a well-thought-out appearance. Hang floating shelves, for example, on each wall but paint the shelves different colors. Alternatively, you can hang photographs or pictures that contain a similar theme but are different colors.