Go to your account page and change your screen name, (account name), by changing your "Nick" name.
At the top of your profile page you will find a link to your account page, it reads "Modify the information about you on your account page.". Click on the highlighted words "account page" and the link will take you to your account page.
Once on the account page simply change your "Nick" name and click the "Change" button when you are done with your alterations.
Return to your profile and refresh/reload the page if you do not see the changes you made to your name.
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CAUTION!!
It is not advisable to make too many name changes. People become confused as to who you are.
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