Core Location: Ground
Being in tune is essential to making sure that we are doing things right and are having a good experience. We have thousands of tuning options (open/alt tunings as well as the standard tuning family).
Our first tuning is typically standard tuning. It, like any tuning, can inform other tunings. 4 tuning options for standard tuning [EADGBE] follow. The relationships are the same for any standard type tuning (most commonly ST-1 which is E♭-A♭-D♭-G♭-B♭-E♭ - this is standard, down a half step).
Listen to each tone (played twice in the track) and match the pitch by turning the pegs.
Each string is struck twice • Low E to High E
Again, standard tuning [low to high...6-5-4-3-2-1] is E-A-D-G-B-E (Eat-Apples-Daily-Goto-Bed-Early). Level out (match) your strings against the sounded tones. Listen for the 'beats' - the wavering of the tone as it approaches the match point.
If this is challenging, just get the low E as best you can and then try tuning by comparing...
A tuner is a device that gauges the frequency (the pitch - high/low) of the strings. It can be a stand alone, one that connects to your instrument (whether clip-on or via cable), or an app on a mobile device.
It 'listens' to the strings, & provides a visual reference for us to tune one string one at a time. This is often the 'easiest' tuning method, but I put it 3rd on the list because we need to learn to tune by ear and we start by trying. Even if we utilize a tuner, we practice other methods of tuning using our ear.
Sometimes recordings can be 'out of tune' with a tuner, or those batteries run out, or we might forget to bring it, so having other ways to tune is important. One of the key points here for using a tuner is that the strings have to be in the range of the tone we are targeting. Reference tones help with this.
Also make sure that the tuner is displaying the correct tone name that we are plucking [EADGBE], & that a flat or sharp symbol isn't being displayed (for chromatic tuners).
I included this last because, at the beginning, this can be an option. Your teacher is typically your first guitar tuner. Yet, a friend or family member who plays is also a possibility. If you are self-studying and don't have a person in your world that can help you, you are your own someone else. Get to it.