How to set shutter speed in manual mode on nikon d5000?

I have a manual focus prime lens. I would like to change the shutter speed.

Added (1). When I attach the lens, I can't rotate the dial to apeture mode. It says that the lens is not attached. I can only shoot in complete manual mode.

Read the instructions that came with your camera. If you don't have the instructions, download them from the Nikon website.

I'd say you're using the wrong lens. Doing manual focus on a dslr is very difficult.

I agree read the book.

Rotating the main control dial should do the trick

Turn the dial. Don't you read the manual? The lens doesn't have anything to do with shutter speed.

In Manual mode turning the command dial should change the speed. Turning it while pressing the exposure compensation button should change the aperture.