visudo question

Ok, I know I'll hear about this, but I have no clue how to use vi. I am trying to add me "jon" to the sudoers file so I can run sudo without the root password. I think I know how to put it in the file: jon ALL=/sbin/mount But how do I save the file?? I am trying to use samba and mount my USB card reader without having to use root password. Thanks for any help.