Reasons for being tired and some solution

Yesterday and today I was tired that I couldn't follow my tasks so I search on youtube "what should I do when I'm tired" and see the first four movies, and now I want to write their tips here:

1- Sleep

 - You should have a good sleep both in quality and quantity.

 - Try to sleep regularly in the cycle of 90 minutes(6h or 7:30') per day

 - No electronic devices in bed

2- Stress

 - This could be about money, relationship, exam, news, etc

 - You could put some flowers or plants in your room

3- Bad food

 - Eating a lot of fast food/sugar

 - No coffee, tea or alcohol 6 hour before sleep

 - Eating vegetable, fruit, nuts and seeds

4- Lack of water

 - You must drink about 8 cups of water per day

5- Lack of sunlight

 - Spend at least some minutes in sunlights

 - Use vitamin D in winter

6- Inactivity

 - Even 20 minutes walk can change

7- Social Isolation

8- Too much exercise

 - Exercising before sleeping

9- Aging

If you have any tips pls write in the comment section. also there is a good book introduction about sleeping in this post(+).