There are three screws labeled on the underside as keyboard you unscrew them however they won't fall out just make sure you unscrew enough then there are four tabs that flip down between the ESC and F1 F4 and F5 F8 and F9 and F12 and Scroll Lock flip them down and the keyboard will lift out.

In most cases the plastic area above the keyboard is removed to reveal the screws for the keyboard. I am unfamiliar with your model laptop, but most have the same concept of how the keyboard is manufactured in. If you could upload some pictures of the area around the keyboard it would help everyone better assist you. It's hard to explain without actually seeing the laptop.

Cheers!

-Varsity

Look on the bottom for some screws with a keyboard symbol. I know the IBM's for one use both screws and sliders and HP may do the same.

Joe is absolutely correct. Unscrew the 3-4 screws that have a small image of a keyboard next to them and then flip the notebook right side up, access the keyboard and pull back (Horizontally) the little tabs that recess into the case from the keyboard to unlock it.

Thanks to this I was able to replace both SODIMMS in my Elitebook 8440p in about 5 minutes.