Time and again, I have pondered what the best vocal exercise could be. Being passionate about getting to unleash a "better singer" version of myself every day, I have encountered a lot of vocal tricks, developed some of my own and have always made it a point that I preach what I teach. Unless I put a vocal trick to work, I never teach anyone about it. (Is it even possible the other way round?)
What's the best vocal workout tip? It's "Ng" exercise. Make the sound "Ng" wherein the back of your tongue touches the roof of your mouth (or soft palate) Sing this on any scale and transpose the melody till you're comfortable. Do this every day and tell me how you feel.