The "rules" of a new job....

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. 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 might be 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. 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.

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.

4. Taking long lunches before you know the lunch culture of your new workplace.
This sometimes trips up people coming from a workplace where hour long 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.

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.

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. Wait until you have a much better feel for your new office’s culture before breaking out even borderline jokes. Even then always proceed with caution.

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. This behavior may not be acceptable later either, it’s always good to ask co-workers or watch their behavior before logging on.

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.