Using your Cort GB - MODERN - 4 - OPCG bass guitar is easy. First, make sure your strings are properly tuned using the Hipshot® Ultralite Tuners. Plug your bass into an amplifier using the MarkBass® MB Instrument Pre preamp system to get the best sound. When playing, hold the bass comfortably and use your fingers or a pick on the strings. As for maintenance, keep your bass in a dry and clean place. Wipe the strings with a soft cloth after each use to prevent corrosion. Check the tuning pegs regularly to ensure they are working smoothly. Also, be careful not to expose the bass to extreme temperatures or humidity, as this can damage the wood and affect the instrument's performance.