I lived in a town of 400 until I was like nine or ten. My dad coached all the sports - he was a gym teacher and health teacher for grades K-12.
In a costume, you need very exaggerated body language - as you say, sort of mime-type skills.
Dream lofty dreams, and as you dream, so you shall become. Your vision is the promise of what you shall one day be; your ideal is the prophecy of what you shall at last unveil.