On Halloween, I got in the spirit by wearing a full body lion costume all day.

I almost chickened out, because I was nervous what people would think as I made my way through the city. While we were encouraging costumes at work, I had to walk about 10 blocks and ride the subway to get there--looking like a cross between Simba from The Lion King and one of those costumed guys who accosts tourists in Times Square.

Would people make fun of me? Would I be embarrassed? Would I run into anyone I knew?

Here's what happened. (In case the short video of me in my costume isn't loading, you can see it here.)

In other words, nothing happened. Nobody cared. I got a slight smile from one guy, a knowing wink from another woman. Nobody else paid me any mind.

That's an important lesson, and one I admit I have had to learn over and over. Whatever I'm worried about on any given day, it's probably totally overblown. Nobody cares!

It's liberating to realize. And, even the few people who do care will soon forget.

All of which got me thinking: there are quite a few lessons I've had to learn over and over. In fact, here are 27 of them.

1. Always take the first step.

How many people do you know who talk and talk about starting a business, for example, but never actually do it? It's called learned inaction. Fear grips you. To heck with that. Success requires taking the first step. Do it.

2. Try 10 things at once.

Why? Because eight or nine of them won't work. And when that happens, you want to be holding at least one winning card or two. I spent two years working on one project (this book), only to have it come out literally on the day that marked the start of the 2008 financial crisis. People were focused on other things, and it affected sales. I made it work, but I sure wished I'd had a few other projects going on at the same time

3. But focus usually on just three things.

Remember, you start with 10 things only so you can test and choose the handful that are most promising. Three seems to be the right number--a rule I first read about 20 years ago--of all places, in Inc. magazine (here--long before I wrote for Inc.com myself).

4. And focus occasionally on 1.

That's the winning pattern: 10 to three to one. Identify the winners, work at them, and ultimately focus your effort on achieving one objective at a time.

5. Your inner voice is usually right.

Whether you call it your intuition, or your conscience, or a guardian angel, it's surprising you often know the right answer to almost any question you pose to yourself.

6. Be open to the 5% of the time when it's wrong.

It's surprising how often your intuition is right--and yet, occasionally, it's wrong. Keep that in mind, and don't grow too cocky.

7. You only get one body.

Take care of it. Exercise, eat right, go to the doctor when something seems off-kilter.

8. Forgiveness is easier to get than permission.

This was Admiral Grace Hopper's mantra, and if you don't know her story, you should take a minute and go read it now.

9. Act.

Fortune favors the bold. Don't be the guy or the woman reminiscing years from now about the time you wish you'd been brave enough to try.

10. Decide.

Decision is the prerequisite to action. Move purposefully through life. There's little that's less attractive than indecision.

11. Sleep on it.

Notwithstanding number 10, there's a difference between being decisive and being rash. I can't tell you how many decisions I've made after thankfully taking 24 hours to decide what to do. (Frankly, I was all set to hit publish on this column two days ago, but I'm glad I took an extra day to reread and edit it.)

12. Forgive.

Most of the time, holding a grudge or refusing to forgive harms you more than the person who seeks your forgiveness. Of course there are exceptions, but they're rare. But don't forget, there's a big difference between forgiving and forgetting.

13. Ask for and accept forgiveness.

Everybody hurts somebody else sometimes. When you do, own up to your mistakes, apologize, try to make amends--and move on.

14. Forgive yourself.

You aren't perfect, not even close. You're not even really supposed to be. So while you certainly want to do your best at everything, forgive yourself when you fall short. Otherwise, you wind up in a weird meta version of the example in #12, where not forgiving others hurts you--only in this case, you're both people.

15. Say thank you.

You want other people to do nice, thoughtful things, right? So when they do so, express your gratitude.

16. Say you're welcome.

Because of it's modern rarity, saying "you're welcome" is probably even more important than saying please or thank you. It's so much better than the "no problem" or "yep" that a lot of people say in response to thanks, because it acknowledges that you think enough of the other person to do something worthy of thanks.

17. Give up your seat.

This is a metaphor for being giving and polite--which costs you almost nothing and makes people like you more. But it's also my daily experience riding the subway (even in a full-body lion suit).

18. Be authentic.

Want to know how to make a good impression on people? Be authentic, maybe even vulnerable. It's so easy to say, and yet so hard to do. There are no real shortcuts.

19. Stay interested.

Interested in what? Other people, learning new things, experiencing new places, challenging your deeply held beliefs. Basically this means living a life that notices and appreciates everybody else around you.

20. Stay interesting.

Be the person who has done or learned something truly intriguing. If nothing else you'll be a lot more popular at parties.

21. Get rid of stuff.

We're Americans. We have a lot of material stuff. Most of it gets in the way.

22. Start with the end in mind.

This is right out of Stephen Covey, but it's smart. If you don't know where you're going, chances are you'll never get there.

23. Embrace the different outcome.

With all due respect to Covey however, to mix my metaphors and make them a bit militaristic: no battle plan survives contact with the enemy; no business plan survives contact with the market. Don't be afraid to find that success might look different from what you originally imagined.

24. Remember who will care the most.

The corollary to the very first rule about how most people don't care--a small handful will. They're probably the key to your success. (By the way, apropos of nothing, I love my readers!)

25. Be part of the solution.

If you voice a complaint, but you don't follow it with action, you're part of the problem.

26. Go to reunions and funerals.

Everybody goes to weddings, but your friends and family really need you at funerals. Reunions are for your benefit.

27. Kids are great.

Since you read to the bottom, you get the best of the list. There is no harder, dirtier, or ultimately rewarding job in the world than raising a child. If you're not a mom or dad, be the best aunt, uncle (official or not) that you can. Honestly, I only had to learn this rule once--but it's one of the most important.