If you still have an egg as your Twitter avatar, it's time to step things up.
Your profile photo is an important part of your online image. Not only is this pic the first thing people see when they look you up on the web, whether you're using Facebook, LinkedIn, or Google+, this image is now regularly transported into people's in-boxes and pulled onto their phones as users rely on services such as Xobni to put faces to their digital networks.
It's worth noting that these images have also moved well beyond tiny digital squares. Facebook, with its Timeline feature, gives you two opportunities to promote yourself--a large cover image and a smaller profile pic. Google+ gives you the option to insert a main image and then a series of images across the top of your account. LinkedIn is more traditional, with room for one photo, but you can manage who can see that picture to include your connections, network, or everyone.
Here are five tips to put your best face forward online.
1. Go pro. You can't go wrong with a professional headshot. Use a solid-colored background and ask a photographer friend or hire a professional to capture your image. For example, Ford's head of social media  has a professional picture with the company's logo embedded in the bottom corner. He also includes his business information beside his photo, and his background image extends his brand, portraying the same look and feel.
2. Be your brand. If a professional headshot is too stuffy for your business, try to capture the essence of what you do in your profile pic. Travel expert JohnnyJet  (@johnnyjet) does just this on his Twitter page. He shares a close-up shot of himself in travel gear on one of his many adventures. His background image is composed of dozens of thumbnails of his many travel experiences, making it very clear that he's not a banker, but a jet-setter.
3. Animate yourself. While I've seen animated profiles go horribly wrong, there is a place for these moving images. Take a look at technology blogger Cali Lewis's banner image . This sequence of professional photos, including the logo from Lewis' online show, help to give her entire page a more professional feel. Also, these moving images make her page stand out from other, plainer-looking pages. To animate your Google+ banner, check out this post on Ghacks .
4. Have fun. There is no shortage of creative profile pics, but some of the most interesting work in this space has been done within Facebook's Timeline. A copywriter from E3, a web design agency in Italy, shows off some extraterrestrial love  in his cover art and profile image. This clever photo integration helps to give his Facebook account a quirky and interesting look. If you plan to use your Facebook account for building your brand, it's a good idea to figure out how you plan to use both of these image opportunities to promote what you do.
5. Avoid the "MySpace pose." As whimsical as it may seem, there is nothing professional about a profile photo you snapped in the mirror on your smartphone. While there is a time and a place for self-portraits, your avatar isn't it; in other words, don't waste this precious real estate on a crummy image. If you want to take your own profile pic, ensure that you use a decent camera, shine light on your face so you're not backlit, and allow for some headroom so your hair isn't cut off. Also, wear clothing that reflects how you would dress in your professional world.
Now it's your turn--say cheese, and don't forget to smile!
For more tips on building your personal brand and working smarter, see Amber Mac's Work Flow series .
[Image: Flickr user Lintmachine ]