Following up on last week’s post of knowing the strings on the guitar: here is how to tune by using your ear.
Start by tuning the low E string. It is great to use either a piano or a tuning fork to match the pitch. Here is a little trick I have found over the years, as it can take a while for the ear to develop: if the piano note is sustained, or in the case of a tuning fork it should be struck and then placed on the body of the guitar, the string will vibrate sympathetically with the initial note. The greater the string vibrates the closer it is to matching the initial note.
These vibrations also occur when we create a unison. Unisons (same note on different strings) are created by fretting the fifth fret of the low E string and when it is played it will sound identical to the A string. The guitar is then tuned using the previous string as a reference to the next string and having the vibrations as a visual aid until the ear develops. Here is a link to a diagram of the fret/string correlation for a unison and a video of someone tuning.
No matter what your level of playing, you will always sound better if your guitar is in tune!