After log-in into your Account, go to the link ‘Your profile’ under ‘Your Menu’ (left site). Move your Mouse over the Button "Edit" (in the upper left corner) and click on ‘Update your Image’.  Then click on ‘Browse’ and select the pic you want from your hard drive. Make sure, that you have the right to distribute this photo! Once you have selected your picture, click on ‘Upload’. Uploading can take a little while, depending on the size of the picture and the kind of Internet connection you have.