Lip trills are one of the best ways to warm up your whole range without straining. The bubbling motion keeps your vocal folds loose while you slide through notes that might otherwise feel tight. If you've ever felt a disconnect between your chest voice and head voice, this exercise helps bridge that gap.
The Sound
Make a "Brrr" sound like a motorboat or a horse sighing. If you can't sustain the trill, gently lift your cheeks with your fingers to take the weight off your lips.
The Feel
Steady vibration on your lips, relaxed throat. Keep your jaw and neck loose.
The Drill
Ascend through 5 notes (1-2-3-4-5), descend back (4-3-2-1), then hold the final note. The classic 5-tone scale warms up your whole range smoothly.
Keep your airflow steady through the whole phrase. If the trill cuts out, you've lost air support or your lips are too tense.