Shúnéngshēngqiǎo, duō liànxí cáinéng tán hǎo gāngqín.
Practice makes perfect. You need to practice a lot to play the piano well.
Tips
memory
熟 (familiar/ripe) + 能 (can) + 生 (produce) + 巧 (skill/cleverness). Familiarity breeds skill - the more you do something, the more skillful you become, like fruit that ripens with time.