“Early” and “late” are relative terms when describing sleep times. Much depends on when you need to or are able to wake up each day, and how much sleep you are getting. There is some variation from person to person, but generally adults need 7.5 to 8.5 hours of sleep per day. Children (5 years old and up) and teenagers will need more sleep than this, ranging from 8.5 to 11 hours. Infants and toddlers will need even more. Choose a bedtime that is early enough for you to get the right amount of sleep, according to your age and schedule. If you want to figure out exactly how much sleep you need or are getting, consider using a sleep journal. Simply record when you go to bed each night and when you wake up each day, and calculate the hours of sleep you had in between. If you record your sleep for a few days or weeks, then you can also calculate your average amount of sleep. Staying up late can be unhealthy when it becomes a long-term habit. Going to bed late and sleeping in can contribute to weight gain and diabetes, correlate to poor nutrition, and other issues. Just acknowledging the importance of your sleep needs can help you start to improve your situation. Not getting enough sleep can have a negative impact on memory, alertness, focus, and other cognitive functions. If you want to succeed in school, work, or other activities, let this be a motivation for you to go to bed early. If you have to pull an "all-nighter" for school or work, clear your schedule the next day so that you will be able to concentrate solely on these tips for going to bed early. You'll need to recover from the lack of sleep.

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Write a summary of the previous text in Indonesian:
Tentukan waktu tidur yang lebih awal untuk Anda. Pilih waktu tidur yang tepat. Pahami bahwa kurang tidur itu tidak menyehatkan. Pahami bahwa tidur dibutuhkan untuk menjaga fungsi otak optimal.