AfterI finished reading "Why We Sleep" by Matthew Walker.

this sentence is a prepositional phrase, rather than a full sentence. For example, let's look at:

1. After dinner, they went to bed.

If we just say "after dinner," we are missing a full sentence.

He's an author, scientist and professional of neuroscience and psychology at the University of California.

we use "a" if the next word starts with consonant sound

if the next word starts with a vowel sound, then we use "an"

He's been known for his popular book "Why We Sleep" - #, the number 1 Bbest Sseller book in Nneuroscience.

the capitalization within the sentence is only required for things like titles, names, and days of the week

The most important action you need is to sleep better, the onlyand this is the main thing that has the most impact onto your health.

"the only thing has the most impact onto your health" is a fragment because there is no predicate

To demonstrate, we have a thing in our body called the circadian clock, which determines when you feel tired, or awake.

commas do not usually separate two items

"determine" needed the "s" because the noun "circadian clock" is singular

We are creatures of habit, which ismakes it difficult when we try to shift our sleep schedule.

or "which becomes difficult" perhaps

So, by Walker's recommendations, if you can only remember one rule, the number 1 rule you should remember out of his 12 recommendations to get a good sleep for health is to go to bed and wake up at the same time, every night, even on the weekend.

combined this sentence with the next one to eliminate a fragment

also, if Walker gave 12 recommendations, it doesn't need to be capitalized unless it's a title of part of the book or something very specifically named

The #1 you should remember of 12 Recommendations to get a good sleep for health: ¶
¶
Go to bed and wake up at the same time, everything, even in the weekend.

Sleeping more ion the weekend won't fix your bad quality of sleep ofduring the weekdays because it's hard to immediately shift your sleep schedule in one day, like night-owl into early-bird.

or "on weekdays"

often verbs take the -ing form when used as nouns.

Consider: I like to run.

the verb is "to run"

Consider: Running is fun.

the noun is "running" and the verb is "is" and the adjective is "fun"

I combined this sentence with the next one because they naturally go together and the next sentence was a fragment

Because it't hard to immediately shift your sleep schedule in one day, like night-own into early-bird.

The safety way is to try to move your bedtime/ wake time 15-30 minutes earlier or later each day.

or "safest"

Or you can try the "3 dDays of Pain" by Andrew Huberman, which you can easily search it on YouTube.

or

Or you can try the "3 days of Pain" by Andrew Huberman; you can easily search it on YouTube.

(You can stop using your alarm to wake up, in some cases it's can causbe more beneficial to your health, and your heart - which I'll talk about more in the future).

or "talk more about"

I was be able to shift my sleep schedule a bit, from 4-6PM into 3:30PM by yesterday, by only trying to change my sleep schedule, didbut I haven't taken any more actions yet.

"haven't taken...yet" shows the reader that it could happen in the future and that it is still important in the present

"didn't take...yet" sounds like it is no longer important or possible in the present

And I was waking up inat 7pm, but then I got exhausted and somehow fall asleep for 1 hour in the mid day.

I will update you on my sleep health, tips I find that works, and how I apply them into my life.

He's an author, scientist, and professional of neuroscience and psychology at the University of California.

He's been known for his popular book "Why We Sleep" - #1 Best Seller book in Neuroscience.

The most important action is that you need to sleep better, the only thing that has the most impact onto your health.

We are creatures of habit, which is why it is difficult when we try to shift our sleep schedule.

The #1 you should remember ofthe 12 Recommendations to get a good sleep for health: ¶
¶
¶
Go to bed and wake up at the same time, everything, even during the weekends.

Sleeping more during the weekends won't fix your bad quality sleep ofor the weekdays.

Because it'ts hard to immediately shift your sleep schedule in one day, like from night-ownl into an early-bird.

The safesty way is to try to move your bedtime/ wake time 15-30 minutes earlier or later each day.

It worked for me, but it was painful xD ¶
¶
Also¶
¶
You set an alarm for your bedtime, not only your wake up time.

And I was waking up inat 7pm, but then I got exhausted and somehow faell asleep for an 1 hour in the mid day.