How to change Facebook Nickname
Step 1: Click on the symbol in the upper right corner of the screen
Step 2: Choose “Settings”.
Step 3: Click “Name” to change.
Step 4: Enter the name that you want to change into, then select “Review change” to preview.
Step 5: You choose one of the available names by checking the circle.
Enter “Password” and click “Save changes” to complete.