How to change Computer Name by yourself ?

1st  Method

1>Open your computer.
2>Select This Pc in windows  10
3>Select My computer in windows 7
4>Right click on My computer
5>Select  change give its name
6>Now restart your system

2nd Method

1. In Windows 10, 8.x, or 7, log into your computer with administrative rights.
2. Navigate to the Control Panel.
   Click the System icon. (If you do not see the System icon, in the upper right corner, switch the view to Large or Small icons).
3. In the "System" window that appears, under the "Computer name, domain and workgroup settings" section, on the right, click Change settings.
4. You will see the "System Properties" window. At the top of the window, click the Computer Name tab.
5. Click Change.... You will see your computer's name listed.
6. In the space marked "Computer Name:", delete the text and enter a new name for your computer.
7. Click OK, then OK again, and then close the "System" window.