Bumper for a fairly big film fest

Have been invited to shoot a bumper for a top ten global genre film fest. The festival director likes a few bits and pieces I have done, spoke to me and invited me to present something. I'd describe it as top 10 within the horror field so the quality will need to be decent.

I'm tempted to do it, would probably fly out to there but have zero experience with 45 second bumpers.

Anyone else done anything like this and if so, what were your experiences?

Haven't made bumper for years, but as a student I had to

What do you want to know?
'Experiences' is kind of broad and I didn't write diaries

It's like anything you make:
you need to know:
- purpose (promo/branding/advertising?)
- content (what should be in it, storywise?)
- audience (to who should it appeal?)

you need to decide
- style
- look
- pace
- rhythm

you need to use
- logo / styleguide
- pay off

You need to get to the core of the fest's Identity and translate it into a bumper.