It's pretty straightforward ;
Get the bike into neutral and get it fired up.
Foot on the brake
Thumb it into first.. (CLUNK!)
Twist the throttle
listen to the engine
When it sounds like it want another gear, give it one...
This is where things get a bit murky... It's a learned situation and everyone will need to get their own feel for the bike. I tend to shift early, and others like to rev the Spyder up to make more power so the choice will be yours. Have fun with the learning process...
I am guessing your getting a new spyder. You should get a dvd with safety and driving tips. The best advise I could give is read the owners manual, watch the dvd, take your time, give yourself lots of room and enjoy.