You do not need long fingernails to play guitar. In fact, it's best to keep your fingernails short! As for the callouses, these may be unavoidable. If you would like to avoid them as much as possible, ask your guitar instructor about lowering the action of your guitar (the action is the distance between your strings and your frets) so that the frets are easier to press down on.
A few years back, I dusted off the ol' Takamine I got in high school to try some 'music therapy' with my disabled son, who was recovering from a massive at-birth stroke. This reignited my long dormant passion to transform myself from a beach strummer to a 'real' musician; however, as a single mom, taking in-person lessons was financially difficult. Then I found Justinguitar! Flash forward to today; my son is almost fully recovered (YAY!), my guitar collection has grown significantly, and I'm starting to play gigs. None of this would have been possible without your guidance and generosity, Justin. Thank you for being part of the journey!
Though this decision can be based on preference, we think the best guitar for a beginner is the acoustic guitar. Classical guitars have a wider neck, which can be hard for younger students or physically smaller individuals to handle when learning guitar chords. Meanwhile, the electric guitar is designed to be played with an amplifier, which comes at an additional cost. Acoustic guitars are simple and require little to no additional equipment, making them ideal for beginner guitarists.
Try listening to different styles of music for inspiration as you learn to play. If you're trying to learn to play by ear, listen to the blues and try to mimic that sound. Blues progressions are especially great for learning to play guitar because it's built on the basics of music theory. Once you learn those progressions, you can start practicing them in different keys, as well.
After teaching guitar and music theory to thousands of students over past three decades, I thought that I had basically 'seen it all' when it comes to guitar instruction. Then I discovered Justin’s website, and man was I impressed! Justin’s caring spirit, attention to detail, vast knowledge base, and especially his lucid, laidback and nurturing style, allow students to fall in love with the learning process. You see, it’s not enough to simply find out how to play a few cool licks or chords. A truly great teacher will make you fall in love with the process of discovery so that you can unlock the best within you. Justin is one of these great teachers, and I highly recommend justinguitar.com to anyone who wants to tap into their best selves.
Minutes 30-60. Practice making the basic 5 shapes. This is probably the hardest part. You gotta put your head down for 30 minutes and remember the chords that are demonstrated below. Once you start getting these shapes down, adding to your portfolio will be easy. You can even experiment with adding and removing fingers– you’ll find a lot of cool sounds here and you’ll continue to discover these for years to come.
Learn how to read tabs. Tabs will have six lines that represent your strings, along with numbers that designate where you should be placing your fingers. The numbers represent the fret in which you need to hold the string down. A 1 means the first fret, a 2 means the second fret, and so on. Numbers in a progression mean that you hold down the first individual fret and pick the note, then move to the next one, and so on in succession. Numbers on the same vertical line are meant to be played together simultaneously as a chord.
Learn how to transition to different chords. One way to become proficient quickly is to learn how to transition between the various chords quickly. These transition periods are often the hardest for beginners to play when they are starting off. The more you practice between switching to different chords, however, the better you'll get at doing it in songs. Practice switching between open chords like G, A, E, and C. 
I have checked out Justin's site and found it to be comprehensive and informative. I have always felt that learning about music and especially music theory applied to the guitar, is helpful in finding your own unique voice on the instrument and expanding your creative horizons. Along with his insight into teaching and his fantastic abilities on the instrument, Justin has created a powerful go-to-place for anyone interested in exploring the instrument to their potential. Just don't hurt yourself.
Private in person guitar lessons with a skilled instructor that is focused on you, your interests, and your progress is the most sought after experience and hard to replicate online. Plus, you tend to learn faster in person. On the other hand, online guitar lessons are quickly becoming popular. The selection of teachers is not limited to those in your geographical area and you can communicate via video in real time with your teacher in the comfort of your home. When filling out your request on Lessons.com, we recommend you select both online and local options, then compare your options and see what works best for you.
Intermediate Guitar Class - Open to all ages, from age three to one-hundred sixty-three, but an audition or permission from the instructor is required. This class is intended to be challenging. Topics covered may include movable bar chords, song forms, repertoire development, fretboard mapping, improvisation, and other advanced techniques. New classes start every month and may be repeated as often as you like. Cost is $85 per month (4 hours).