Crowhugger has the silver key: Practise. But listen to yourself as you do, do not just regurgitate lines.

Next. The gold key is simple but harder: If your subject engages you, motivates you, let the audience feel it. Communicate your enthusiasm.

Imagine Bruce Lee talking about a side thrust kick. "Not just fast, not just hard, not just perfect form, but also EMOTIONAL CONTENT!"

Good Luck, Fortunato