OK here goes. I hope this works, my father was a little vague on it. I don't think he takes his apart unless it completly fails to work.
First of course make certain there is no amunition in the gun. Mag removed and chamber checked. I know your not an idiot or anything but you never can tell.
He says, 1. pull the slide all the way to the rear.
2. lift up on it while sliding it forward.
Thats it. I hope it works out for you. Mayby someone who has one in his hand will reply here if I'm wrong.