By adding a picture to your profile, communication between others on the site is much more personal. It adds a level of trust for the person you're communicating with and for those viewing your profile. All around, it's a good practice to add a picture to your profile. Here's how:
1.) Login to to the site and click "Edit Profile" from the top dropdown menu.
2.) Once there, click the button that says "Upload from computer."
3.) Select your photo and upload
You're all set! Now others can see your profile photo during any communication you have on the site and on your public profile.