If you spend a lot of time with acoustic guitar playing you will need to pay attention to your posture if you want to avoid back problems. There is a lot to learn when you are first starting out so we will talk about a few of the tricks of the trade when it comes to holding and playing your guitar the right way. Take your instrument and hold it so the back is touching your stomach. The neck should be to the left if you are right handed. Put the curved part of the bottom of the body on your right thigh. Next you will need to take a hold of the neck with your left hand and put your right arm down where the strings go over the hole. This is a good starting position but if something does not feel right feel free to adjust to suit your body.All of you out there that are right handed should be using the left hand to press down on the strings. Bend your left fingers so that you can press down on the strings so they will sound good and clear. The way the back of the guitar neck is curved allows your hand to be comfortable when playing. This will allow your thumb to move around to different positions so you can play at different places on the neck. You can place your thumb either on the back of the neck or along the side depending on what you are playing. In the beginning choose the position that feels best to you.While all of this is going on with the left hand your right hand will be busy picking or strumming the strings. Your right arm should be comfortable on top of the guitar. A good place to strum is right over top of the sound hole. This oversize hole in the top is where all of that beautiful music will come from. A lot of guitarists prefer to use a pick when playing. Hold the pick gently but firmly between your thumb and forefinger. Then you will want to drag the pick across the strings to begin playing. If you are a left handed musician there is no need to fret over all of this, as there are options for acoustic guitar playing for lefties. One thing you can do is restringing the guitar in reverse. Another thing that you can do is purchase a special guitar made for a left-handed person. Proper technique will allow you to spend extended amounts of time picking. Do it right and your acoustic guitar playing will not only sound better it will also be easier to actually do. Take the time to learn to do things the right way and your body will thank you for it.