Roll your head slowly from side to side to release tension in your neck. Relax your facial and neck muscles, and stand up straight and tall. Good posture and a relaxed body are important when you are warming up because these factors help you to sing with more accurate pitch and with greater control.
Softly vocalize a series of notes that are comfortable for you to sing -- not too high or too low. When you vocalize, hum the notes at first. Go up five notes in a row within a scale and back down the same five notes.
Sing vowel sounds on ascending and descending notes. You can use a consonant of your choosing as you sing. For example, you might sing, "mah, meh, mee, moh, moo," on the same note. Then move up in pitch by a half step and sing the same sounds again. Slowly work up and down your vocal range.
Warm up your lips by singing rapid, short notes on five ascending pitches and then back down the same pitches. You can use a nonsense sentence to help with this, such as "Mama met me on the moon last night." Start on at least 8 to 10 different pitches as you repeat this exercise.
Sing an airy "Hooooooooooo," starting on a high note and allowing your voice to trail downward as you exhale on the tone.