In a tight job market, it’s important to stand out – but not for being unprofessional.

What’s the most unprofessional thing you’ve ever done at work?

The first habit to avoid is being late. One survey found 15 to 20 percent of United States workers report being tardy on a regular basis.

Another unprofessional trait -- being negative all the time. A CareerBuilder survey found 62 percent of employers are less likely to promote employees with a pessimistic attitude.

Also, avoid being messy at work whether it’s your desk or in the break room. About 36 percent of employers have a hard time promoting employees who don’t clean up after themselves.

Cursing is another no-no. More than half of employers in a survey said vulgar language is an indication that an employee is not ready for a promotion.

Some other common mistakes are bragging too much, not paying attention during meetings, soliciting donations, discussing personal problems, making personal phone calls, complaining, and practicing poor hygiene.

Gossiping and being too cliquey are also unprofessional behaviors. Nearly half of employers said they would think twice before promoting an employee who participates in office gossip.