It’s not easy to land an internship in this competitive labor market, and for students fortunate enough to land a coveted spot, the hard work is just starting.

Internships provide an inside glimpse of the world of different industries, and while it is a learning process and mistakes will happen, students need to be on the top of their game if they want to be considered for a future full-time job.

“Employers know through experience that whatever they’re seeing in these early stages may only manifest themselves into more later on and it’s such a red flag to them—am I going to have to do even more coaching?” says J.T. O’Donnell, career strategist and founder of Careerealism. “If you make some of these early mistakes and your peers do not, you’re losing points; meaning the other folks in the internship are going to get the job offers before you do.”

However, making a good and lasting impression is important regardless of whether or not interns are seeking a permanent place at the company, explains Heather Huhman, founder and president of content marketing and digital PR firm Come Recommended

“Internships are stepping stones to future careers,” she says. “Even if the company is not somewhere they want to work in the future, it is still essential to leave the right impression because your supervisor is the person who will recommend you to other employers.”

To ensure they are putting their best foot forward, here are the top four mistakes career experts say interns make and what they can do to avoid them.

Mistake No. 1: Being too Casual

While interns should strive to fit into the office environment, there is a fine line between feeling comfortable in the office and being too comfortable, warns Huhman.

“You want to portray yourself as professional throughout your entire internship--things like texting, browsing social media, and dressing casually indicate you are [too] comfortable where you are,” she says.

While it’s important for interns to act naturally and show off their professional personality, they should treat their internship as an extended interview in terms of their everyday behavior, says author and career coach, Miriam Salpeter

“Just as in an interview you would dress a certain way, sit a certain way, your conversations would be somewhat guarded in terms of what you share,” she says.

Mistake No. 2: Avoiding Company Events Outside the Office

Forgoing company dinners, networking events and staff outings may cause interns to appear less than interested and committed to their position, warns Nathan Parcells, co-founder and CMO of InternMatch, an online platform matching college students with employers.

 “It’s important to attend as many after-hour events as possible to get in valuable face-time with your coworkers, expand your network and prove your investment and interest to your employer,” he says.

Although interns may feel anxious about holding conversations and networking  out of the office, getting practical experience is the only way to feel more at ease in professional situations, says O’Donnell.

“Say to yourself, ‘I’m going to go to three events: I know it’s not going to be easy but by the end of the third event, I’m going to know how these things work, I’m going to have a few conversations and not be nearly as stressed as I feel right now.”’

Mistake No. 3: Not Owning Up to Mistakes

Asking thoughtful questions along the way can help prevent careless errors, but interns should accept that mistakes are bound to happen in a learning environment and that they can grow from them.

“Some of the best learning experiences come in the form of mistakes,” says Parcells. “Employers should understand that their interns are there to learn and mistakes are just part of the process.”

Rather than trying to cover up a mistake or hope no one notices, interns should be straightforward with their supervisors and suggest a plan to rectify the error, says O’Donnell.

“Go in, take full ownership and accountability and come up with a game plan of how you think you can fix it, present the plan and say, ‘because of the situation, I didn’t want to do it without checking with you first.’” 

Mistake No. 4: Not Keeping in Touch

An internship might end after a couple months, but that doesn’t mean communications should. It’s much easier to ask for a job down the road if students don’t have to resume contact from past employers.

“Maintaining these relationships is important for recommendations in the future, or even returning to the company,” says Huhman. “Even if you touch base every few months, it is a good idea to continue this so your supervisor remembers you--you never know when your relationship will impact your future.”

O’Donnell suggests former interns stay on top of industry events and create a calendar reminder once a month to reach out via email to their employer and keep them in the loop. 

“Send your contacts an article or two and say, ‘I’ve been keeping an eye on the company, I saw this article and it made me think of you all, school is going well’--it’s just a friendly reminder that says I’m still thinking of the company, I’m still paying attention and I’m still doing my thing,” she says. “That’s how you stay on their radar screen and you show them how proactive you are.”