Nikon D40-manual mode difficulties?

Alright I have an older D40. Most of the time I shoot in shutter priority, but I'd prefer shooting some things in manual. I only have one command dial--how do I change both shutter speed AND aperture? I spin the dial, and it only lets me change one (I'm pretty sure shutter speed.) What button/menu do I go to so I can change the aperture as well? I've done it with no problem on several other camera bodies, ones with two command dials (D90 and D7000.)

You need to hold the button with the aperture symbol and then turn the dial. The details are explained in the manual. If you lost yours you can download one here: http://www.nikonusa.com/...oprint.pdf