If you don’t mind taking advice on the subject–from a woman, here are a few tips!
Relax. Even when you’re wearing a suit (it might take practice).
Hold doors open for people.
Be aware of your surroundings.
Don’t overwork. God gave you a body to use for His glory, not to destroy.
Keep secrets—even if you don’t understand why it needs to be a secret.
Be good to everyone—even people who make themselves your enemies.
Don’t use slang that is jangling to the senses of other people.
Don’t use slang that you wouldn’t care to have to explain to someone who isn’t familiar with it.
For the most part, just don’t use slang at all. That is, use more normal English than you use slang.
Say “thank you.”
Say “Ma’am” and “Sir.”
Say “excuse me” when you need to get by someone.
Don’t intentionally confuse or embarrass people.
Easily admit that you are wrong.
Think before you speak.
Pray before you act.
Clean up. It isn’t ungentlemanly to get dirty (or greasy) but it is ungentlemanly to stay that way longer than necessary.
Pay attention to your appearance . . . in such a way that your appearance requires very little attention from you.
Say what you mean and mean what you say.
Say a great deal less than you think.