Light, light, light.
Nothing says tiresome like a dim room. Think about it. We fall asleep to darkness, so how would anyone ever be productive without a strongly lit environment? While natural light is best, an online post by UNC Kenan-Flager Business School reports that cool lighting, such as blue tones, “increases work performance by supporting mental acuity, vitality, and alertness while reducing fatigue and daytime sleepiness,” as it lessens melatonin levels.