You know the importance of a first impression. As a jobseeker, a first impression was very valuable; now that you’ve accepted a job offer, first impressions are again of critical importance.

First impressions about people often turn into long-term perceptions and opinions. This works well for people who make positive first impressions but can be a negative for people who make negative first impressions.

“I think the early days are when your boss and colleagues form the most lasting impressions about you,” said Ann Marie Russell, a program coordinator with AmeriCorps. “This is when they make assessments about your ‘typical’ behavior, and what ‘type’ of person you are.”

“If you have any attendance or punctuality issues in the first few days or weeks, you’ve already lost a significant battle — their confidence in you. People will take you as seriously as you seem to take yourself and your work,” said Russell.

During those first days in a new workplace, where you are meeting your new coworkers, first impressions about you and your future potential can make a major impact on your success with the organization.

1. Have a Positive Attitude
Nothing works better to improve people’s first impression of you more than having a positive attitude. Let your enthusiasm for being part of the team and the organization show through to everyone you interact with. Leave your personal problems at home and concentrate on radiating your excitement for this new opportunity.

2. Dress Professionally
You should never underestimate the importance of dressing professionally. Studies show that people make a judgment about you within seven seconds of meeting you, and the way you dress can impact this impression significantly.

In the beginning, take care to dress professionally even on casual days. In the early days of a new job, you just never know when you’ll be called out to meet a top manager or key client. “Perfectly groomed means efficient and reliable [in people’s minds]; unkempt means disorganized and therefore difficult to trust with different assignments,” said Desiree Devaney, a financial analyst with GE Capital Credit. “After awhile, people realize these things do not necessarily correspond, but initially, your looks and dress are your representation to them.”

(For more about dressing for success, read How to Make the Best Impression in Your First Days on the Job.)

3. Show Your Team Spirit
You are now part of a work team, and teams work together to solve problems and get the job done. Show loyalty to your co-workers by focusing more — initially, at least — on sharing recognition with the team. Always give credit where credit is due to gain the trust of your coworkers.

4. Learn Coworkers’ Names Quickly
No one expects you to have everyone’s name down pat by the end of the first day or week, but if you are bad with names, now is the time to research some memory-aid tricks you can use to help you remember your coworkers’ names. Make it a priority to learn the names of every member of your team. And if you are in a situation in which you forget a person’s name, the best solution is simply to apologize and ask again.

5. Ask Questions/Ask for Help
No one expects you to know everything when you first start a new job so feel free to ask questions or ask for help when you need it. Remember that it’s better to ask for clarification before you’ve spent time completing a task the wrong way. It can be easy to let pride get in the way when you first start a job but pretending you know things you don’t isn’t the wise path. Listen to your coworker, ask questions and communication openly with your supervisors about any concerns that arise. No one expects you to know it all in the first weeks and months of a new job.

6. Take Notes and Go to Orientation
Unless you have a photographic memory — and few of us do — take notes on all the systems and rules of your new organization. Attend all orientation sessions and accept any training that you are offered. Nothing will get you up to speed at a new job faster.

7. Take Initiative
In most situations, you will be given small doses of work at the beginning of a new job. Starting slowly allows you to get your feet wet without getting overwhelmed. As you finish assignments and are ready to handle a bigger workload, take the initiative and ask for more assignments.

“Be proactive,” said Ali von Staudach, senior account executive for CNET Networks. “Don’t wait for an assignment. Stick up your hand and ask for something to do.”

8. Learn Everything You Can About Your New Employer
In theory, you should have already done your homework during the interviewing process, but there is always a lot more to learn once you’re on the inside. Get an employee handbook and study it. In addition, gather all those reports and company literature and read as much as you can to become an expert on your organization.

9. Arrive Early, Leave Late and Don’t Call in Sick
“Be on time, come in early, stay a little later,” said von Staudach. Remember, you can’t be a go-getter and clock-watcher at the same time so plan to be at work a little longer than your eight-hour shift. There’s nothing that can affect your reputation faster than routinely coming into work late or leaving work early. Especially in these first days or weeks on the job, observe the flow of the office and be sure you are coming in earlier and leaving later than the majority of your coworkers. Also, don’t take long lunches, especially in the beginning. Once you understand the office culture better, you may be able to shift your hours or take longer lunches but in the beginning, err on the side of spending more time at work to make a great first impression.

10. Establish a Good Attendance Record
It should go without saying that it’s important to show up to work every day and establish a good attendance record. Yes, there will be emergencies, and, yes, you may get sick, but as best you can, try to make it to work every day during those first weeks and months on the job.

11. Avoid Office Politics and Gossip
The workplace can be full of rumors and gossip. Your mission should be to stay above the fray. Take care not to associate the office gossips and don’t get involved in any office trash talk or politics, especially in the beginning. Repeating gossip will do nothing to help you make a good first impression at a new job.

“Stay out of the office politics for as long as possible,” Magennis says. “It’s inevitable that you will be exposed to them sooner or later, and you will most likely participate in them as well as it’s human nature. But stay out of the game for the first few months.”

12. Keep Personal Business on Company Time to a Minimum
Studies show that just about everyone conducts some amount of personal business on company time — checking email, making dinner reservations, buying stuff online. Your goal is to keep your personal business to a minimum and stay focused on work. If you need to make a personal call, step away from your desk. If you need to make a reservation or take care of other business online, do it quickly and discreetly, and, if possible, from your personal device.

13. Take Advantage of After-Hours Activities
Many organizations have formal or informal after-hour activities, such as sports leagues. Get involved — even if only as a cheerleader — because these types of activities are great ways to bond with your coworkers. Do be on your best behavior during these outside-work activities, though.

“If attending happy hours with co-workers, never drink more than one drink,” suggests Anne Johnson, senior corporate relations coordinator for the U.S. Chamber of Commerce, recalling a coworker who came to a happy hour and had too much to drink. “Now, no one will invite her again. You don’t want to make a stupid mistake like that.”

by Randall S. Hansen, Ph.D., and Katharine Hansen, Ph.D.