You are now a professional - write and talk like one
Simply put: being unprofessional is when you saying or writing things you shouldn't say, or write in the workplace: content, format, or style. For example, in most workplaces you should not use street slang, cute email emoji's, text short forms, and definitely nothing vulgar, and no 'swearing'.
Your mood or emtional state can be important! How do you feel prior to a conversation? Are you upset? Are you excited?
If you are upset, have you considered taking a minute to process your emotions? Journaling might help, going for a walk can also help.
Building a habit to stop, process, then communicate can be useful in training your mind to move past sharing initial reactions which may not always be appropriate.
Professional communication is not small talk, idle chit-chat! What is the purpose of this chat? Are you seeking advice? Are you reporting information? Are you trying to solve or avoid a problem?
If seeking advice – are you seeking advice from a peer? A mentor? A subordinate?
Are you aware of who is around you as you're talking? Who might overhear bits and pieces of your conversation?
What would someone passing by think if they heard something out of context discussed in your conversation?
When communicating, are you clear, concise, concrete, correct, coherent, complect, and courteous? [1]
Specifically
Clear
Is your objective clear? Are you using appropriate language complexity depending on who you’re chatting with? For example, an engineer may understand more scientific terms than a non engineer. Have you checked to make sure that the person in the conversation understands what you’re explaining?
Concise
Did you get to the point in a straightforward manner? If trying to be sensitive or use indirect communication – are you using too many filler words and sentences?
Concrete
Are you using specific examples? Do you have any figures or facts to support your message? If in a report, make sure those figures are properly explained to show the trend you’re trying to demonstrate.
Correct
Did you verify the information you’re sharing? If from a site – did you cross reference? Did you use reputable resources? If calculating or formulating graphs from data – did you double check your formulas and your numbers? Did you do a sanity check?
Coherent
Do your verbal or written massages make sense? Proofread all emails to make sure everything makes sense. If in person – check with the person if everything you’ve explained makes sense. Repeat in a different way if it didn’t make sense.
Complete
Does your message include all the necessary details? If communicating to someone for the first time about a project they weren’t previously a part of, are you explaining all the basics, so they are aware of all the details? Avoid assuming someone knows something you haven’t explicitly mentioned.
Courteous
Are you using your manners? Saying please, and thank you goes a long way.