How To Tune A Guitar

The first thing you should do every time you pick up your guitar is tune your instrument.  Your guitar will fall out of tune very time you play it; it's a natural result of a variety of things such as regular use of your guitar and various environmental factors.  You can do everything perfectly with your hands when you're playing a song but if your guitar is out of tune, it's likely to sound a bit unpleasant.  You want your strings to be in tune with each other so there isn't any unwanted dissonance.  To put it most simply, dissonance is when a chord doesn't sound quite right.   You may not notice dissonance all that much when you start playing, but as you practice more your ear will pick up on more details and you'll start hearing it more.  You may find that you start to enjoy it when it's used in certain ways, but for now it's largely something to be avoided because it can be difficult to control.

The musicians who have a lot of gear likely have a pedal that they use to tune their guitar, while more minimalist or casual musicians often have a clip-on tuner that they attach to and detach from the head of their guitar as needed.  Either of these should be available at a local guitar store, or you can order them online if you'd prefer.  Tuning pedals are typically going to be more expensive than clip-on tuners which perform the same function, although clip-on tuners can be difficult to work with when you're in a room with other musicians who are playing because their sounds will vibrate your guitar and alter the frequency being read by your clip-on tuner.  I wouldn't recommend getting a tuning pedal until you have a pedal board and some other effects pedals, because setting up a single tuning pedal will be much more effort than just attaching and detaching the clip-on tuner.   There's also a third type of tuner you might find that isn't quite a pedal where you plug your guitar into it but I find that these aren't very well-designed because you don't want to constantly plug and unplug your cable from your tuner to your amp.

If you don't have any of the above, you can tune your strings relative to each other so they're in tune as a single instrument, but you shouldn't rely on this method if you're playing with a group because there's a variety of factors that make this method inconsistent and you'll end up being out-of-tune with the rest of the band.

FACGCE is also an open alternate tuning which is popular in folk music and more niche subgenres like math rock and Midwest emo, recently popularized by bands like American Football who sit in the intersection of Midwest emo and math rock--two closely intertwined genres.  To tune your guitar to FACGCE, you will need to tune your 6th and 2nd strings up by a half step (one fret), while tuning the 4th string down a whole step (two frets.)

Drop D tuning is a popular alternate guitar tuning where the pitch of the 6th string is lowered by one whole step from E to D.

The primary benefit of Drop D tuning is that it allows guitarists to easily play power chords with one finger on the lowest three strings, which can create a heavier and more aggressive sound than standard tuning.  Drop D tuning is used in a variety of genres but it's primarily associated with rock and metal.

To tune down to Drop D, simply tune the 6th string down a whole step—you can do this by matching the pitch of the 7th fret on the 6th string to the pitch of the open 5th string.

Open D tuning (also called DADGAD) is an alternate guitar tuning that has become popular in folk music. It's an open tuning, which means that when you strum all of the strings without fretting any notes, it produces a pleasant chord.  This tuning has a bright, beautiful sound.

To tune your guitar to DADGAD, you will need to lower your 1st, 2nd, and 6th strings by a whole step (two frets), while keeping the 3rd, 4th, and 5th strings in their standard tuning.

D Standard tuning has the same intervals between the strings as E Standard so it sounds the same as normal standard tuning except it's tuned one whole step lower.  This tuning can give you a darker, heavier timbre and sound.