I would never open up the camera and try to clean the sensor on my own. There’s just too much of a risk. Cleaning the lens, on the other hand, is something that you can do at home. Just get a clean, dry, lint-less cloth (like a microfiber cloth) and rub the lens. If you just apply a bit of pressure, and some elbow grease, your lens will be clean and unscratched, like new.