Sage green can serve as a common thread between wallpaper and the rest of a room. To avoid an overly uniform look, play with variations in value, textures, and small touches of color.
Decide on the role of green
Decide whether sage will be the main color of the decor or a subtle accent. With large green foliage, keep the larger furniture in simple tones. With a light background punctuated by leaves, a sage armchair or curtain can become the link between the wall and the room.
Compare the shades in situ
Two greens bearing the same name can look very different. Place the wallpaper, paint, and fabric samples side by side. Look at them in daylight, then in the evening with your usual lamps.
Add texture in other ways
Light wood, an ecru textile, and a small touch of brown are enough to enrich this palette. If you prefer a more graphic atmosphere, try a few fine black elements. Keep the most pronounced contrasts for objects that are easy to move before committing to a large piece of furniture.