Open a Terminal window and type:

`sudo visudo`

In the bottom of the file, need to add the following line:

`$USER ALL=(ALL) NOPASSWD: ALL`

Where $USER is your username of your system.

for username type `whoami`

now paste the code

`kahnucharanswain ALL=(ALL) NOPASSWD: ALL`

press Ctl + x to exit nano and it'll prompt you to save).
Save and close the sudoers file
(if you haven't changed your default terminal editor (you'll know if you have),