Good manners should be used all the time - at work, home, anywhere. Manners shouldn't be a "management tool" but in the pressure of a regular work day it's easy to forget and take co-workers and customers for granted.
I focus on 10 words - 2 phrases really - that I try to use to help me be successful. These work well no matter the situation or circumstances.
Here's the first situation: Imagine you are a manager, with real people reporting to you. Your boss, Mary, asked you if that critical project is still on track. "Get back to me as soon as you can" she says. You're smart enough to recognize an immediate shift in your priorities and you know where the information is. You couldn't get to the latest project update meeting but Sam did. But he's working on something else at the moment - You could barge into his cubicle abruptly and declare "Sam, Mary asked me for an immediate update on the project. I know you were at the last meeting so tell me what's going on. I need it now."
That would be wrong on several levels. You'd likely get the information and it probably would be accurate but any positive relationship you had with Sam just left the building. Permanently.
On the other hand, imagine if you knocked on a solid part of his cubicle to announce your presence and started the conversation like this: "Hi Sam, Would you help me please?" It sounds much better already. It's particularly effective if the person you are speaking to believes that you are sincere. (more on sincerity later). So that's the first phrase - Would you help me please.
The second phrase is the reverse of the first - you're still the boss but someone comes into your work space. You are up to your eyeballs responding to Mary's recent request and you see Roberto at the edge of your vision. (Remember that open door policy you said you always have?) You don't know what he wants but his body language is clearly "we need to talk." You say "Hi Roberto, How can I help you?" You never know what information is going to walk in your door, and you need to be receptive to it. After all, it could be a more recent update to the project that Sam was not aware of. That's the second phrase - How can I help you.
A quick story about how I once responded - incorrectly - to a situation similar to the Roberto situation just described: A manager who reported to me appeared at my door wanting to talk. I saw her out of the corner of my eye and waved her in as I was hanging up the phone. She explained her situation but I was focused on the phone call. She could tell I wasn't really paying attention and was out of there in 4 nanoseconds. I knew immediately that I had made a serious mistake - she never came by just to chat - and I raced back to her office, apologized and asked her to please walk me through the situation again. We laugh about it now but it wasn't funny. She had information that I needed, she knew that she would tell me at some point before anything got worse but if I wasn't going to pay attention then she would come back later. She was right. Imagine if I started the conversation like this: "Hi Eileen, how can I help you?" I would have been focused on what she was telling me, and I wouldn't have wasted her time. Eye contact is also critical - staring at your smartphone and grumbling in an irritated 'how can I help you' tone doesn't convey an attitude of attentiveness. Many would call it self absorption and they'd be right.
Sincerity = credibility. If you're the kind of person who is a little rough around the edges when it comes to interpersonal skills (and you know who you are), then transitioning from a barking drill instructor to respectful colleague will take time. For awhile your employees may think it's an act. Most will be willing to take you at your word and give you a second chance. We all need second chances. No one is perfect and even the best of us fall down. The key is to get back up and keep going. What's the harm in trying to be better? Almost everyone can see someone who is insincere coming a mile away. Don't be that person. To do your job well you need to be credible.