On Youtube you can find excellent tutorials on the application of stage make-up so let us focus on the basics. Stage light can make your face look flat and your skin kind of lifeless.
Always use foundation. Even a flawless skin can look quite hideous on stage without an even layer of pan cake. However avoid moisturizer. Dancing under those hot lights can become quite a sweaty business and you will want to avoid a shiny nose and forehead. Your aim should be an even powdery/satiny canvas to paint on.
Now your face looks even flatter which is good. 🙂 Use blusher and concealer in lighter and darker colours than your skin tone to ‘sculpt’ your face. You can accentuate your cheek bones and modify your jaw line in this manner.
Remember that the jury and the audience see you from a distance and that people in general are attracted to the eyes. Make sure your eyes and mouth are really visible by using eyeliner, false lashes, highlights and glitter & gloss on the right places. Brownish colours tend to look muddy under stage light, so use a bright red for your lipstick.
And a final word of advice. On stage there is no such thing as too much make-up. Cosmetics that would be totally inappropriate in the workplace, can be perfectly fine under the spotlights