1. None of your decisions are important. I'm not saying that to belittle you. I'm saying it because you can worry yourself sick if you're afraid of doing the wrong thing. Life is a balance between "analysis paralysis" and jumping into things too quickly.

You should lean toward jumping too quickly. Even if you make some small mistakes, be open-minded and willing to learn from them, and you'll be able to recover.

It takes many years of compounding a mistake before you're unable to recover. Career-wise, it probably can't happen until you're 45+ (due to age discrimination).

2. Whenever possible, take your career in a direction that allows you to be paid more for working fewer hours. This will pay off later in life when you have the money to travel or just want to see loved ones.

There are many ways to accomplish this. One of them is to ask for better-sounding titles, even if they don't come with more responsibility or pay. Another is to develop skills that are widely applicable, rather than highly specific. The worst thing you can do is to develop skills that are only applicable to your specific employer.

For example, I have a lawyer friend who worked on a lawsuit related to microprocessors. He did this for five years. When he wanted to move to a different firm, no one wanted to hire him because he only had experience with microprocessor litigation.

If you're starting out as a developer, try to work somewhere that uses modern, popular technology. Both of those are important: modern and popular. For example, a company that exclusively uses Haskell or Scala is probably not a great idea. You'd want to get experience at something like Python, C++, C#, Java, or JavaScript instead. (Note that the culture of companies that use Java extensively are often very poor, so make sure to read Glassdoor reviews or ask HN about the company).

3. Sleep. If you focus on doing one thing at a time, you'll be way more efficient than your peers, and you'll have time to sleep 8+ hours a night. Don't work at a company that expects you to sleep less than 6 hours a night and spend all your time at the office. They're living in the past and don't understand that overall output suffers when people don't get to rest.

4. Build and use your social network. Don't be afraid to ask friends, parents' friends, relatives, and strangers to help you. If you don't have many friends, go out of your way to make more.

My life is exponentially better because of only 2 friendships that I randomly made a few years ago. It's been literally like winning the lottery. But you have to meet a lot of people and make a lot of friends before you find those relationships.

5. Your career isn't and shouldn't be your life. If you can't have an interesting conversation with someone that doesn't mention your job, you're doing something wrong. Have hobbies and other interests.

In that same vein, ask yourself (or old people) what someone might regret toward the end of their lives. Absolutely no one will say "I wish I'd spent more time working". Virtually all of them will say "I wish I'd spent more time with my family/friends/pets/hobbies". If you don't believe me, go out and ask.

6. Leave your comfort zone whenever possible. The more you practice it, the better you'll get at it. Every amazing thing in life requires being vulnerable and leaving your comfort zone.