I learned about this from Andrew Huberman’s podcast which is available completely free of charge. You can also find him at Hubermanlab.com where there’s a really good search function.
View sunlight by going outside within 30-60 minutes of waking. Do that again in the late afternoon, prior to sunset. If you wake up before the sun is out and you want to be awake, turn on artificial lights and then go outside once the sun rises.
On bright cloudless days: view morning and afternoon sun for 10 min; cloudy days: 20 min; very overcast days 30-60 min. If you live someplace with very minimal light, consider an artificial daytime simulator source.
Don’t wear sunglasses for this practice if you safely can, but contact lenses and eyeglasses are fine.
No, you don’t have to look directly at the sun, and never look at ANY light so bright it is painful to view! That said, you can’t wear a brimmed hat, sunglasses and remain in the shade and expect to “wake up” your circadian clock.
Get as much light exposure as you can during the day. Either go for a walk, lots of short walks, eat your meals outside, or sit next to a bright window.
AVOID light exposure between 10pm and 4am, and wear an eye mask if there is any light at all in your sleeping area.
Some people need to reduce light exposure as early as 8pm, so see what works for you.
Using candles at night instead of electric lights will help this, and use low level lamps that light your working area as opposed to using overhead ceiling lights that brighten the entire room.
Dimming the lights in the lamps or using low wattage bulbs with an orange glow will also help.