Get up and make it happen.

The old expression about "thinking on your feet" is one that is so colloquial we never give it much thought but consider the abstract though that the expression is not "thinking on your butt" because we can all think and speak better on our feet rather than in a chair.

Getting on your feet will help you make it happen because on your feet your mind and voice simply function better. (As long as you aren't trying to do three other things at the same time.)

Standing up during important phone calls is one of the time testes strategies employed by successful people in all walks of life. For you, it starts with your voicemail greeting. Always stand while creating your greeting. Your voice will sound better and you will sound more confident. And the same goes for any conversation where you have to be your best. Stand and deliver.