1. Don't emulate your worst-dressed colleague
Just because you saw someone in accounting wearing flip-flops, doesn't mean you should dress like you're going to the beach. Many organizations encourage comfortable attire, but be careful not to be too quick to try to win the "worst dressed" team member award.
2. Don't give off a "don't talk to me" vibe
Maybe you don't really like people, but if you don't want to be considered a problem employee, you need to appear approachable. If you walk around with a sour expression, arms crossed in front of you and fail to make eye contact with your colleagues, it may just mean you're having a bad day or you're very shy. However, you'll quickly earn a negative reputation that will be difficult to overcome. Smile, even if you don't feel like it or if you are having a bad day.
3. Don't be a slob
At home, if you want to challenge yourself to see how high your piles of junk can get before toppling over, that's up to you. At work, especially in shared work spaces, it's important to maintain a neat workspace. If you appear sloppy, people may assume you aren't organized and can't handle important responsibilities and you'll find yourself in a dead-end job.
4. Don't be a bully
Maybe you were one of the "cool kids" and have a tendency to make fun of people, either to their faces or behind their backs. In the workplace, that can be considered bullying, and can be grounds for being fired in some cases. Regardless of the laws in your state or expectations at your workplace, you aren't likely to win many friends when people worry they may be your next target.
5. Don't spill your guts
Do you tend to overshare? At work, it's best to keep yourself in check and find other people to tell the long, drawn out story of your bad breakup, sex life or wild, partying ways. Keep conversations friendly and professional and keep your personal drama to yourself.
6. Don't talk about how busy or tired you are
No one cares how busy you are. Everyone is busy, and your job is to get the work done. If you are exceptionally overwhelmed, it's a good idea to have a conversation with your boss and to ask for some help, but most of your colleagues will quickly tire of hearing about how busy and overwhelmed you are at work.
7. Do not spend your day on personal calls, texting or posting to social media
When you're at work, phone calls should be work related. At most offices, it's acceptable to have some personal interactions on the phone, but if your friend/child/mother calls you five times a day, it's up to you to table those calls to after hours. The same goes for texting and updating personal social media sites.
8. Don't be the first one to leave
Everyone will judge your work ethic based on when you run for the exit. Do not close up shop at the earliest opportunity if you want to make a good impression. "Face time" is more important at some companies than others, but if you work in an office, make sure you're doing everything you can to help out and to be available to help others before you bolt for the door.
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