Good question.
Here comes a good answer:

Basics in life:
1. Think, speak, act morally. Set up strict moral standards and follow them strictly. So you are not afraid of death.
2. Avoid greed and anger. Learn only beneficial things.
3. Help others when you are healthy.

Practicals:
4. Intermittent fasting, no junk food
5. Moderately active lifestyle. Moderation matters.
6. Hang out with people with above 5 qualities.

Wish you would not live life in vain.