Using these D'Addario EJ48 strings is easy. First, loosen the old strings on your classical guitar and remove them. Then, thread the new strings through the bridge and the tuning pegs. Tune the strings to the right pitch. When you're playing, you'll notice the bright acoustic tone right away. As for maintenance, after each use, wipe the strings with a clean cloth to remove sweat and dirt. Keep them in their corrosion - resistant packaging when not in use. And be careful not to over - tighten the strings, as it might damage them or the guitar.