To change your personal URL handle go to your profile settings. Click on your name in the upper right corner and select profile. Find the field called “username”.
Your URL handle is tied to your username (username has nothing to do with login). Just enter new user name and click SAVE.
Note: Your username or URL handle is public so choose a username wisely or with good judgement.
Username can not have more than 40 characters and only letters, numbers, dash - or underscore _ can be used