How Will I Know by Sam Smith is in C at 82 beats per minute and runs 3:54 across 71 bars. It uses 8 chords — C, F, G, Am7, Em7, Dm7, G#dim, G7sus4. The chord diagram changes as the song plays and the words light up as they are sung, so you can strum and sing along without reading ahead.
Want the melody line note by note? How Will I Know guitar melody tab.