"Keep your back muscles open."
"Every note is important."
"This is Italian, you're singing too French. This "non" is not French "non," it's Italian "non." Every language has a different sound."
"When you jump to high note, kick air up from stomach."
"When you perform live, mix up the empos of the songs. Not just fast-slow, but unpredictable sequences."
Homework: "Maria," from West Side Story: practice the tempo and blending head sound with chest sound. Pay attention to how Carreras makes the "ah" sound. You don't have to do it totally Puerto Rican, but make the "ah" sound in "Maria" rounder, like Carreras.