There are a couple of things that you should always remember when you are a beginner, and that is to constantly practice to become a great guitar player and to keep your instruments in tune and perfect condition. Tuning a guitar using your ears is a very difficult process especially for beginners. This skill takes a lot of time to master and perfect. Such special skill needs a lot of patience and perseverance before it can be mastered. For the mean time, you need to use an acoustic guitar tuner so that your instruments would sound right so it can complement your plucking skills.
Acoustic guitar tuners come in different types. One of the most common types of acoustic guitar tuner that you would encounter is the electronic acoustic guitar tuner. The needle of the electronic tuners indicates whether the string is either flat or sharp. If the needle points to the center, the results mean that the tune is perfect. If the needle yields to the left or to the right, it means that it is either high or low. To make sure that everything is in tune, a green light will flash if you play the scales. The strings would need some turning if red light appears on the acoustic guitar tuner.
The other acoustic guitar tuner that has a built-in microphone is the acoustic guitar auto tuner. The string of a standard guitar is calibrated for this acoustic guitar tuner. There is no need to play the scales, all you need is to play the note and it tells whether you are out of tune or not.
The other type of acoustic guitar tuner is the clip-on tuner. There is no need for a microphone since all it needs is to pick up the vibrations of the guitar while being clipped on to it. This is suitable when you are playing to a full house and you want to check your guitar in between songs.
You can avail of these acoustic guitar tuners at your local music store but make sure ask around what is the suitable one for your particular situation.