Using these D'Addario EJ87C ukulele strings is easy. First, tune your concert ukulele to the standard GCEA tuning. You can use a tuner to make sure each string is at the right pitch. When you play, you'll notice the bright tone and great projection. As for maintenance, keep your ukulele in a dry and cool place. Wipe the strings with a clean cloth after playing to remove dirt and sweat. This will help the strings last longer. Also, be careful when changing the strings to avoid any damage to the ukulele or the strings themselves.