1)Click windows button in the keyboard.
2)On the top right corner of your START SCREEN we have username, right click on the username or just click on it.
3)It will shows options like Change account picture, lock, Signout. Click on Change account picture.
4)It will takes to a page where all the details of your PC details will be displayed.
5)On the left side you will see many settings among them select 'USERS' .
6)On the Right side you will see under 'SIGN-IN options' we have an option CHANGE YOUR PASSWORD click on it.
7)If you have system password it will ask to enter the current system password and click on NEXT button.
8)Then it will promt you to enter 'new password', 'reenter new password' and 'password hint' .
9)After entering all the details click on NEXT button and Then click on FINSH button.
10)That's it, if you log into the system for the next time You can log in with the new password
Watch the tutorial video you can easily understood.