Boat Launching Procedures

So here it is.

I just bought a new boat and decided to take 'er for the maiden voyage this past weekend.
This is my first boat and I wasn't quite sure of the exact Standard Operating Procedures for launching it off a ramp, but I figured it couldn't be too hard.
I consulted my local boat dealer for advice, but they just said "don't let the trailer get too deep when you are trying to launch the boat".
What am I doing wrong?
Well, I don't know what they meant by that as I could barely get the trailer in the water at all!







Anyhow, here's a picture below. See for yourself. What am I doing wrong?