Cleaning my nikon D5000

My camera has recently been saying that no lens is attached, i have looked around for the cause of the problem and most forums suggest cleaning the contact points however i'm unsure how to safely clean this part of my camera, any suggestion on how to do so without damaging my camera would be appreciated!

Take it to a camera store and have them clean it. Unless you are a millionaire and can afford to damage the camera and throw it away.

Using the tip of a pencil eraser is usually the best way to clean the camera/lens contacts. Just make sure that no 'bits' fall into the camera body.

This may shock you but in the Owner's Manual for your camera there's a section on care and cleaning. Read it and heed it.

Before you do anything, I'd try removing the lens and then putting it back on.