When you're new to a job, you're subject to a whole different set of rules than you are once you've been there longer. Co-workers don't know you well yet, so small behaviors can carry more weight. Actions that might go unnoticed six months down the road can raise concerns about your work ethic, reliability and judgment.
Here are eight things that you shouldn't do when you're new to the job -- but that are OK to do later.
1. Asking for vacation time during your first few months. In most cases, taking time off soon after starting a job will raise eyebrows. Your manager is likely to think, "She just started, she's still being trained and she already wants time off?" Exceptions to this are if a close family member is seriously ill or if you cleared the time off before accepting the job.
2. Complaining to your co-workers about your new boss. Frankly, it's not great to complain to your co-workers about your boss no matter how long you're been at your job -- but when you're new, it comes across as especially tone-deaf. Even co-workers who aren't your manager's biggest fans are likely to be put off by it, simply because complaining so early on signals that you're likely to be a prima donna who doesn't even settle in before finding fault. Similarly ...
3. Bad-mouthing your old job or old boss. Once they know you better, your new co-workers might be thrilled to hear your war stories about your crazy former boss or your nightmare cubicle-mate at your old job. But if you share that stuff when you're new, you'll just come across as someone willing to bad-mouth colleagues. People are more likely to think, "Wow, that's going to be us she's talking about one day." Wait until you know each other better before you break out the work horror stories.
4. Taking long lunches before you know the lunch culture of your new workplace. This sometimes trips up people coming from a workplace where hourlong lunches were the norm and are moving to an office where people take half an hour or simply eat at their desks. When you're starting a new job, it's smart to observe the lunch culture for a few days until you have a feel for your new office's norms. It's also fine to ask a co-worker, "What do people normally do for lunch?"
5. Pushing the envelope on business expenses. As the new guy, there's no faster way to torpedo your reputation than asking to stay at a more expensive hotel during business travel or rent a nicer car. Once you've established yourself as a great employee, you might be able to get away with arguing the merits of these things -- but if you try it as a new employee, it will define you in a way that will hurt you.
6. Using bawdy humor. It might never be OK to do this in your workplace, but there are certainly some offices that have a higher tolerance for risqué humor than others. However, if you plunge right in without getting to know your new co-workers better, you risk alienating and offending people if you've read them wrong. Wait until you have a much better feel for your new office's culture before breaking out even borderline jokes. Even at that point, proceed with caution. Just because you've seen one person doing it doesn't mean that everyone else is comfortable with it.
7. Spending time on Facebook or other social sites. Once you've proven yourself as someone who works hard and produces high-quality work, it might be entirely fine to take the occasional Facebook break. But when you're new on the job, being spotted on time-wasting sites is likely to make your co-workers -- and especially your manager -- worry about your work ethic.
8. Calling in sick during your first month, unless it's truly dire. Rightly or wrongly, if you call in sick while you're new on the job, your manager is likely to worry that it's going to be the start of pattern and that you're not reliable. Of course, if you're truly sick and especially if you're contagious, you might have no choice. In that case, you should make it clear that it's an unusual occurrence. It doesn't hurt to add, "I'm mortified that this happened during my first month." The idea is that you want to reassure your new manager that this isn't the first of many absences.
Alison Green writes the popular Ask a Manager blog, where she dispenses advice on career, job search and management issues. She's the author of "How to Get a Job: Secrets of a Hiring Manager," co-author of "Managing to Change the World: The Nonprofit Manager's Guide to Getting Results" and the former chief of staff of a successful nonprofit organization, where she oversaw day-to-day staff management.
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