Ukuleles are quite portable as far as musical instruments go, but there’s another instrument you’re always in possession of— your voice! So why not sing while you play? Every time you sing, you’re training your ear to hear the melody (even if you’re stumbling to find the right notes) and paying closer attention to your tempo. My own experience has taught me that a voice is like any other instrument—just as your uke playing can improve, so can your singing. So give it a try. You’ll probably have more fun if you do!