Always Keep Your Strings Clean
For anyone who notices that your strings wear out prematurely because maybe you have sweaty hands or if you just want your strings to last longer, I’ve noticed that washing and drying my hands thoroughly before playing really lengthens the life of my strings.
Also, wipe off your strings when you’re done.
Storing Your Guitar
Remove some but not all of the tension from the strings, clean & polish the guitar, and then put a little lemon oil on the fret board. Put the guitar in its case and store it where it won’t get too warm, cold, or humid and won’t get bumped around. A good place is an interior closet.
When changing guitar strings, it is best to change them one at a time starting with the thickest. This keeps the tension on the instrument and you will have less trouble getting it in tune because the guitar doesn’t have to stabilize again.