
I have been playing guitar for 5 years now, and a recent purchase inspired me to take better care of my instruments. Caring for your guitar gives you much better long term benefits, it makes your instrument last longer in every way. The proper level of care will ensure that your strings retain their tone for longer periods, lower fret and neck wear, whilst keeping the instrument as a whole looking great.
There is a common belief in the guitar world that an instrument with chips and dents makes it vintage. While I partially agree with this statement, I also believe that a well kept, well aged instrument looks a whole lot better. (Besides, there is no need to bash it about needlessly just so it looks 'Vintage'.)
There are four key elements to keep your chosen guitar in the best condition possible.
Casing
For the same reason you would not go climb a mountain in trainers, you shouldn't take your guitar anywhere without the proper equipment. There are two main types of casing: hard cases or soft cases. Where possible, you should always invest in a hard case, as they offer superior protection for your instrument.
If you transport a guitar using a soft case it will often knock it out of tune, which means you will have to re-tune your guitar unnecessarily. As an additional downside (as I have learnt from experience), if your strings were not cut tightly to the pegs then the interior of the soft case will degrade through being repeatedly scratched by sharp string ends.
Clean Hands
It might seem like a strange thing to do, but even if you have washed your hands earlier that day, your hands build up oils which can degrade the quality of the strings faster. It is a good practice to wash your hands (and ensure they are properly dry) before you start playing guitar.

I often see these 'kids' with guitars in gig bags and wonder how long the guitars will last.
If you are spending real money on an instrument it is really worth you looking after it.