First: Keep it Simple: Don’t try to do every run or lick in the book. Just sing from the heart and try getting out some long tones from the very beginning. Nerves and especially emotions always affect you ability to breath fully and correctly. If you can breath and hold some long tones right up front it will help get the breathing rhythm to slow down and get back to where it should be.
Second: Pause when you need to: Take a moment if you need it. Collect your focus and go on with your song. Don’t feel like you have to rush. It was a great call to let her sing the first part by herself so she could get into a performance zone and rhythm. Then once she had taken the time she needed to get comfortable out there with what she was doing, they brought the piano player in.
Third: Keep your gesturing to a minimum: She just sang the song and let the emotion hit everyone. She didn’t try to put on a big diva show. She let the moment really be about Whitney Houston.
Fourth: Don’t try to copy the way the artist sang the song: This would have been very tempting on a huge song and moment like this, but she sang it the way she felt it. Never once appearing to try to out Whitney, Whitney. Sing the song the way you feel it in that moment and please, please, please sound like yourself, not like you are trying to copy the artist’s version of the song.
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Fifth: Give a respectful and collected shout out to the person and those on stage with you: Please don’t fall apart at this moment. Keep it short and simple, if it is very emotional for you, you will be close to needing to let it out, but find it within yourself to keep a possible impending breakdown from happen on stage. You are there to honor someone else. Don’t make your audience suddenly have to focus on you. This is difficult, but if you have found the strength to make it through the song, you can make it off stage. Remember you were picked because you are professional. Not always an easy task, but you can handle difficulty and stress.