Disable password for sudo command has its risk and convenience so do assess the risk for your environment before disabling it.

I usually disable it in my test/lab environment as the risk is lower there and I do not want to keep entering password for sudo commands. Of course you can use root account to configure your lab as well.

Enter the editing mode for sudo configurations.
sudo visudo

For a single user you can use the following command.
<username> ALL=(ALL) NOPASSWD: ALL
e.g kelvin ALL=ALL NOPASSWD: ALL

For all sudo users you can modify the %sudo config to include NOPASSWD: ALL
%sudo ALL=(ALL:ALL) NOPASSWD: ALL