The fact that we only live once doesn't mean you can do anything you feel like.
There are a lot of things to learn from life but you don't have to know everything in order to live the right life. This should give you a reason to say never to many things;
1. Never ignore your parents
Whether they made you who you are or they did completely nothing towards your career, never have a reason to ignore or disvalue them. Especially if they struggled to get you where you are.
Neither should you forget about them because they had no ability to educate you. They are meant to be valued no matter what.
2. Never ignore your health
Your health matters more than any other thing. You need a good health in order to live the longest life.
Do as many things as you can so you can be healthy in every aspect of life; physically, mentally and emotionally.
3. Never say "I can't" to everything that looks difficult
Success and breakthrough often come from things that look difficult. It is time you change your attitude towards things.
Not everything that seems difficult to you is actually impossible. Replace your "I can't" with "why not" and you will witness an adventurous life.
4. Never have zero goals to aspire to
Do not live a poor, goalless and unproductive life. Come on! You didn't come to this world to live and get helped all along.
You have a reason to live. This means you need to set goals for yourself to work towards.
5. Do not let your past define how you see yourself
People who let their pasts define them never see that there are a lot more to do in life.
Life is like a continuous exploration, such that you learn from the past so you can get to change and achieve new and better things.