Almost from the moment we’re born, humans have a visceral attraction to faces. It takes us only a split second to assess someone else’s mood or nature by subtle changes in their facial expression.

That’s why it’s important to get our business profile photo right. The web is no longer the anonymous place it once was. We are all out there marketing ourselves, and for better or worse, our micro-portrait avatars stand for who we are.

Yet plenty of professionals fudge the chance to present themselves in their best light. Here’s how they do it—but shouldn’t.

1. Take the photo from really far away.
In an already-tiny picture, 85% of the real estate gets taken up by the least important element­—the background. I can’t tell anything from a face that’s the size of a peppercorn. I want to see your eyes. If I can’t make that immediate human connection, I wonder what you’re hiding from, all the way back there.

Tip: Crop the picture from just above the hairline, to a little below the chin, keeping your eyes in the top half of the frame. I don’t need to see your chest, or for that matter, the top of your hair. Ah, now I can see you much better. You’re not that bad looking after all.

2. Whatever you do, don’t smile.
The thing is, even a neutral expression can appear to the camera as a vaguely hostile glare. All I need to see is a warm, confident, professional smile and I’ll peg you as a warm, confident professional. Mouth slightly open, but please, no toothy, pasted-on grin with the corners of your mouth jacked up to your ears. This isn’t your 8th grade school portrait.

Tip: Yeah, smiling can be hard when you’re on the spot. Try turning your head away from the camera; then, when cued, turn back to the photographer as you flash a genuine, unself-conscious smile. Maybe pretend he’s some cherished, long-lost friend who just walked in. Mmm, that’s better.

3. Face the camera straight-on for that “mug shot” look.
No, no, no. Position your body on an angle from the camera, then turn to look at the photographer for a more casual over-the-shoulder look. Since most profile photos appear to the left of your posts and updates, angle your shoulders toward YOUR left when being photographed.

Tip: When cropping the shot, leave a little more space on the right side, where your face is, and a little less on the left, behind your head. That’s it, perfect.

4. Have a cluttered and uneven background.
Odd-shaped distractions in the background of your picture will compete with your face for attention. This is your professional portrait, not a vacation photo. A simple flat or gradient background makes you the star of the show.

Tip: A white or very light photo background, when seen on a white page background, can make it seem like your head has been chopped from your body and your scalp has been chopped from your head. Not a pleasant look, so go a little darker with that background color. Good, good…watching those details makes a difference, doesn’t it?

5. Send a rectangular photo to fit a square space.
When you do that, the bottom part of the picture will automatically get cut off. Seeing only the top half of someone’s head makes them look like a five-year-old at the Thanksgiving dinner table. So send a square to begin with and avoid unpleasant surprises.

Tip: The largest your profile photo will appear (on your profile page) is 200 pixels by 200 pixels, which translates as about 2.75 inches square at 72 ppi. So that’s what you should upload; for actual posts, the picture will be automatically reduced in size as needed.

Let’s face it: we judge each other, consciously or not, based on what we see. Our internal sense of trust is drawn to an honest, close-up smile, but is repelled by an unsmiling mug shot buried way back in a messy background. When was the last time you did business with someone you didn’t trust?