How do you properly use red light glasses?

Wear red-light glasses in the evening after sunset to filter short-wavelength light from screens and indoor lighting, helping protect the evening melatonin signal and support the transition to sleep. 1

• Don’t use them during the day: They’re intended for evening and nighttime, not daytime blue-light filtering. 2
• Dim overhead lighting and use dim red lights: Reduce evening light as much as is practical and safe; shifting to red lighting can help limit stimulating short-wavelength exposure. 3
• Switch to red lighting about an hour before bed, if possible: The guidance describes using red lights for the last hour of the evening; the glasses themselves can be put on after it gets dark. 4