good evening ladies and gentlemen, I am here to talk about the greatest scam, global warming, err climate change ......that's a good first sentence

How about this intro :

glub glub glub

It is 2150 AD and I'm drowning in 8 meters of water because of a sea level rise due to global warming.

That aught to set the stage for the talk.

Wear a Soccer Goalie suit? (just guessing)

As an introduction, how about:

It was the best of lies, it was the worst of lies.

I have to do a sppech about global warming but I dont have any ideas on how to do a introduction.

my ideas on the paragraphs are:

First paragraph: What is Global Warming?

Second paragraph: Causes and long term effects

Third paragraph: Solutions and what I do to help

Thank you :)