If you don't get a professional photographer, you want to keep a fairly neutral background with very good lighting. Dixson says people do use to eliminate wrinkles or unflattering features, but be careful: future employers will want to meet you in person for an interview and that picture will set their expectations for what you look like. While this is not supposed to matter, we all know it does.

Lastly, on the issue of timeliness, it can be tempting to leave pictures up of your younger and perhaps better-looking self. Dixson says while you don't need to update your picture every year, it should still match up pretty well with your current appearance.

"If people are going to meet you and be surprised by the difference, it's time to get a new one," she says.

2. Summary

When you read a newspaper or check out articles on a website, many good stories don't get read without a good headline. As such, Dixson recommends that you be very concise, engaging and specific in the summary field of your LinkedIn page. If the summary doesn't draw people in, all the great gigs you've had over the years (listed in the "experience" section below it) might not receive any attention.