Warm-ups are incredibly important for professional athletes, dancers, and other professionals who are involved in physically strenuous activities.

Professional voice-over involves a lot of strain on your vocal cords. So warm-ups can help you prepare your voice for a flawless performance.

A seasoned voice narrator will usually perform warm-ups on two separate occasions: once in the morning, and often right before a live recording.

When we wake up in the morning, our voices are usually not at 100%. A short warm-up will help clear your throat and get you ready for the daily grind.

And live sessions are incredibly demanding situations where you need to put your best voice forward. This makes a quick warm-up immediately before a session well worth the effort. 

Lip rolls and trills are a popular exercise among professional singers. If your voice-over work involves a wide range and diverse vocal registers, these exercises will help you sharpen those.

To roll your lips, close your mouth and create a constant "B" sound. This will vibrate your lips, creating a trilling sound effect.

Tongue trills involve similar mechanics, but instead of the lips, you will be vibrating your tongue. To achieve this, keep your mouth comfortably open and try to create a "G" or "D" sound with your tongue pressed up against the roof of the mouth. When done correctly, the tip will vibrate, creating a trilling sound effect in the process.

 A typical warm-up for voice-over can last anywhere from five minutes to well over 20 minutes.

You can fill up all those minutes with a choice selection of sound exercises for your mouth. Some of these require you to keep your mouth closed, while others give best results when you keep your mouth open.

Remember to keep a constant pitch and move through your vocal range only gradually.