...[500 days and counting
Change the strings regularly! And learn how to do this properly so the strings stay in tune.
If you have a $100 guitar new strings only help slightly, but if you have a $200-$300 guitar like mine or even a $10 000 guitar, please remember that it will still sound like poop when you have tired strings that are out of tune.
Last time I put on extra durable strings - which was really a mistake unless your calluses are the size of marbles
- and right now I am using Martin steel strings "Silk and Steel"
which is like having a whole new guitar
One really good piece of advice I got from this thred was to put together a little kit - spare strings, wire cutter, pin puller - and stash it in the guitar case. Another good tip was to tune the guitar at least EVERY DAY if not every time you sit down. With a cheap electronic tuner and a fresh set of strings, there is no reason to sound like poop [unless your guitar truly IS a piece of poop
in which case please accept my condolences].