The keys are drinking a lot of water and getting enough sleep.
Your body needs to be constantly hydrated and get enough rest. Don't push your body to it's limit like not sleeping or not getting 4-8 hours of sleep everyday. you may not notice the effect but it would show gradually and badly.

Do not eat to much instant food and with preservatives.
Eat healthy like leafy veggies and meat to get nutrients and proteins

Exercise at least 30 minutes a day to have a good heart and

Smile <3