Uncork Capital
A couple of things to do before getting into your demo or presentation

My buddy Ed Sim has posted a piece that I recommend anyone doing a company, financing or product pitch to read: Don’t forget that vision thing. This paragraph sums it well:
As one of our marketing consultants, Richard Currier, has always told our portfolio companies, “you market the vision, and sell the product.” If you get too locked into talking about a product, then your partner or customer gets stuck into thinking about who else does this and why are you different. Getting into a feature/function battle in the first meeting is not a great way to start. Sure enough, our prospective partner started naming several companies asking us how we differed from them. If you start with a vision first and clearly talk about your view of the market in the future and how your product evolves from where it is today to a roadmap of the future, then it is easier to differentiate your company and bring the discussion to a higher level.
Too often do I sit in presentations or pitches with a company, and we end up diving in a deck or a demo without even getting two critical pieces of context: background & objectives.
Background: introduce the company in a few sentences, and simple terms, covering history, vision and team.
Objectives: establish what your motives are for this meeting, and how you are suggesting to conduct it.
Spending 2 to 3 minutes on setting up the context sort of brings everyone on the same page, and focuses attendees on fact gathering. I made a similar comment after Demo 2006 when I liveblogged about 68 companies (!!!): companies that did not give attendees a context really represented a challenge when trying to write about them.
A collateral benefit on setting up the context of such a presentation is that it can be more or less scripted, which allows people who have a bit of a challenge kicking off a speech to practice.