https://www.musical-u.com/learn/how-to-tune-your-guitar-by-ear/
A lot of discussion can be had over whether the guitar should be tuned by ear or with the help of an electronic device. As we’re about to see, tuning by ear has multiple benefits over the “easier” path of using a tuner. https://www.musical-u.com/learn/how-to-tune-your-guitar-by-ear/