Give your audience just enough to whet their appetite, and spark their interest, yet not so much that they get lost in the details. Leave them wanting more.
Speak with passion and enthusiasm about your project - if you're not enthusiastic about the film, why should anyone else be? And know your film inside out - because if you get past the pitch stage, there'll be questions and plenty of them.
Also, if there are any "name" cast or crew attachments, mention them in your pitch. Name dropping is perfectly fine in this situation.
"It's about dreams, guts and glory. It's a story of love, loss, jealousy and betrayal, set against the backdrop of motorbike road racing. Jeremy Stanford is to direct. Nicolette Freeman is DP. It's Days of Thunder meets Chariots of Fire. Its a story that could be about you, me, anyone on this planet - a story that celebrates believing in a dream and the ultimate triumph of the unconquerable human spirit."
"Its about believing the unbelievable. A story of love and loss, revenge and redemption, myth and magic. It is about an ordinary woman in extraordinary circumstances. A story that encourages you to live in the moment, believe in yourself, trust what you can't explain, love despite the odds and ultimately, finding through your past, the key to your future. Its about discovering and embracing your destiny."