As a society, we put a lot of weight on physical appearance. We may not realize it, but how someone looks heavily determines how we respond to them, whether it be a potential future partner, or someone we may hire as a financial advisor. That’s why when you’re looking to post your default photo on LinkedIn, it’s important you do it right. This is not just the first image a future employer will see of you when scouring the net for prospective employees, it may be the only picture she sees of you, so make sure you look professional, while somehow conveying a go-getter attitude. But how exactly do you tell the employer of your dream job that you’re a natural-born leader, but can still work well in a team environment in just one photo?

A new study conducted by researchers at New York University found that the trick to looking like the perfect employee in your LinkedIn photo is to look happy…but not too happy. Researchers found that people who looked a “little” happy in their pictures made the best impression. Apparently there is a balance to be found between enjoying yourself too much and not enjoying yourself enough, and you somehow have to embody it within this one photo. So what exactly does a “little” happy look like?

According to the study, slightly happy photos show people who are not smiling outright, but just slightly. They are not dying of laughter, but instead possess a positive, confident expression with upturned eyebrows and lips, reports Time. Employers find that individuals with relaxed, upward expressions are more reliable than those with more stern expressions in their picture. In fact, they are less likely to trust someone who adopts a more serious expression on LinkedIn.

In one of the experiments conducted by the study, researchers presented participants with images of faces, and asked them who they would choose to be their financial advisor and who they believed to be a weightlifting champion. Most participants chose those with slightly happier expressions to work with their money, while those with more serious expressions were chosen to lift weights. So if the job description you’re applying for does not read “Future Arnold Schwarzenegger” than maybe you should refrain from the latter face structure.

The effects of appearance on your employer don’t stop there, though. Another study conducted by researchers at the University College London and the University of Maryland found that men who were slightly less attractive were more likely to get jobs than their more attractive counterparts. This especially held true for jobs in more competitive markets, like car dealerships, because employers found attractive men to be more intimidating, and thus imposing to their future sales.

Business Insider, unsurprisingly, found the opposite when it comes to women. In an Italian study, researchers found attractive women had a 54 percent callback rate for follow-up interviews, compared to the average 30 percent.

So what does this all mean for you, and your LinkedIn profile? When taking your picture, be sure to aim for happy, but not too happy. Look professional, and competent but do not look serious. Try and look appealing, but do not border on intimidating. And most importantly, be yourself. You can manage that, right?

Source: Lee S, Pitesea M, Pillutla M, Thau S. When beauty helps and when it hurts: An organizational context model of attractiveness discrimination in selection decisions. Organizational Behavior and Human Decision Processes. 2015.

Hehman E, Flake J, Freeman J. Static and Dynamic Facial Cues Differently Affect The Consistency of Social Evaluation. Personality and Social Psychology Bulletin. 2015.