Strum your guitar with a pick or your fingers. Hold down the strings with your fingers in the appropriate shape and try to strum with your other hand. Acoustic guitar strings often have higher actions than electric guitars, so you may have to press down very hard to get a good sound. If the chord comes out muted, try holding down the strings with more force. If your string is buzzing, move your finger further away from the metal fret on your neck.

Play Guitar! turns your Windows 8 machine into a virtual guitar. You can press and strum strings, just like a real guitar. Play Guitar! helps you learn what notes lie on the frets of the guitar. It is a very useful tool for every aspiring guitarist. Now, there are available an advanced chord editor and the possibility to use guitar capo (only for PRO users, In-app purchase) The app is easy to use and light.
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.
I have heard how giving you are in so many respects of music schooling and I must say that I am impressed. You remind me of the pure idealism that we had in starting Apple. If I were young, with time, I'd likely offer to join and help you in your endeavours. Keep making people happy, not just in their own learning, but in the example you set for them. 

3/4 Size Acoustic: I also have a 3/4 Scale Guitar in my apartment because they are awesome to sit beside your couch and just pick up easily and jam with. I bought the guitar a few months ago, and when I was playing it a concerned shopper came up to me and reminded me “that’s for kids you know.” I laughed. Fair enough, but I think little guitars are cool to have around the house, so if you do too (or if you have really small hands) perhaps this could be the guitar for you.
Learn the difference between chords and single notes. Chords occur when you play two or more notes on different strings simultaneously to create one unified sound. These are what make up the "rhythm" portion of acoustic music. Single notes are used more for solos and occur when you play a single note at a time. Both are skills that you must become proficient in when learning to play the acoustic guitar.[4]
C-chord: Place your ring finger on the third fret of the fifth string. Place your middle finger on the second fret of the fourth string, and your index finger on the first fret of the second string. Strum all but the sixth string. Then, go back and play each string individually, while still playing the chord. Make sure each string rings out clearly.

Make-up Policy - 24 hour advance notice required to receive make-up credit. Make-up lessons may be either private or group lessons, based on your instructor's availability. If an instructor misses a lesson for any reason, a full cash credit will be applied to the following month's tuition. If you must miss a lesson, please be courteous and give your instructor as much advance notice as possible.