Don't criticize, condemn or complain.
Certainly don't condemn, that's just being a dick.

Be careful about criticising, will that really and I mean really help?

Complain? Trying to stay positive is good for your mental health. Never complaining, not so much. Completely hiding your feelings is bad for one of the most important things in life: Making a true and honest connection with other people.

Give honest and sincere appreciation.
Or to put in a more general way, seek honesty and communication.

Arouse in the other person an eager want.
Aha! This must be the secret to influencing, but.. uhm... how do you do that exactly?

Become genuinely interested in other people.
Sure, again seek genuinely human connections, that's a good thing.

Smile.
:)

Remember that a person's name is to that person the sweetest and most important sound in any language.
Not for me, you can call me anything as long as you're good to me. A great old guy completely screwed up my name once, to the point of calling me a completely different name.
By the time I realized he was NOT talking to someone else, it was in front of company and I didn't want to embarrass the old man. He kept calling a name which was 100% not my name, but he was a great guy! I like that guy a lot. So yeah, what ever. It's not about the name, it's about showing you care about someone, the name's just a small part of that.

Be a good listener. Encourage others to talk about themselves.
In other words, interrupting people is rude, and talking too much is also kind of a dick move.

Talk in terms of the other person's interests.
Communicating with others is honestly hard, it really is.
One "trick" you can use is try and frame things in a way the other person can understand, use metaphors invoking things they like etc. As you communicate with someone the understanding between you and them will grow and you can communicate more with less effort.

Make the other person feel important - and do it sincerely.
Oh I bet that's another secret, and how do you exactly and sincerely make people feel important? All I can guess is listening and communicating without treating them a like an inferior.

The only way to get the best of an argument is to avoid it.
Sure don't be that guy that looooves arguments. Unless you're having dinner with Brits, arguments are just damn good fun, it's bad if you can't hold your own!
And some, in fact often the most important arguments can NOT be avoided. In fact, a pathological avoidance of arguments will in the long term NOT make you popular.
The above rule can be put more simply as: "Don't be a dick."

Show respect for the other person's opinions. Never say, "You're wrong"
Don't be a dick.

If you are wrong, admit it quickly and emphatically.
Be honest, communicate, don't be afraid of failure or embarrassment.

Begin in a friendly way.
Don't be a dick.

Get the other person saying "yes, yes" immediately.
And how do you do that exactly? Do you open with: Is the sun bright or what?

Let the other person do a great deal of the talking.
Don't be a dick.

Let the other person feel that the idea is his or hers.
Or maybe you should seek agreement, and try and make them see things your way and tell them how their way of thinking inspired yours, and don't be a manipulative sociopath.

Try honestly to see things from the other person's point of view.
Don't be a dick. Be honest, communicate... I feel like I'm repeating myself.

Be sympathetic with the other person's ideas and desires.
I am repeating myself.

Appeal to the nobler motives.
Yes appeal to things which are good and legal, not damaging and/or illegal things.

Dramatize your ideas.
Communicating with other is really hard. You can't just dump a succinct thought in your head and expect everyone else to get it.

Throw down a challenge.
Or offer something that's fun. Just don't bring people down and don't be a dick.

Begin with praise and honest appreciation.
Positivity, honest communication, etc.

Call attention to people's mistakes indirectly.
Don't be a dick, but do be honest and sincere. Don't be an obtuse prick, people do appreciate honest communication.

Talk about your own mistakes before criticizing the other person.
Don't be a dick.

Ask questions instead of giving direct orders.
Use the Socratic method of teaching. If you can that is. That shit ain't easy!

Let the other person save face.
Don't be a dick, and try not to embarrass people.

Praise the slightest improvement and praise every improvement. Be "hearty in your approbation and lavish in your praise.
You might not want to "make it rain" with cash, but verbal recognition cost you nothing so the ROI is like infinite.

Give the other person a fine reputation to live up to.
Yes, when most people think you don't think much of them, they'll meet your expectations.

Use encouragement.
Didn't we just talk about that?
Make the fault seem easy to correct.
Don't be a dick, be honest but positive and don't embarrass people.

Make the other person happy about doing the thing you suggest.
The best you can do is invest a lot of effort into honest communication and making the other person feel respected and that you think of them highly. And then try to tell them why what you suggest is important to you and try to communicate your ideas as best as you can, dramatically, with things they are interested in, etc.

And if that's not enough, you're screwed. But maybe they'll still do it. Just don't be a dick or a sociopath.

Now recently I by accident (pointless small talk before a meeting) found out my manager and I share a common interest.
We've been talking about it often because we enjoy talking about it.

And recently I also mentioned I wished one of the projects I'm on had him as a manager, but I was also happy he was happy not be part of that cluster fuck.

Yet I've never red "How to Win Friends and Influence People" and I haven't seen this website before today.

All I try to do is:

1. Not be a dick.

2. Be honest.

3. Be positive.

3. Avoid fear, embarrassment, false pride, etc.