Shoot with lower ISO settings. This is a trade-off which reduces the camera's shutter speed and increases its f-settings. The camera should not be used to capture images at low light with a low ISO setting.
Download the latest firmware for you camera. The newest firmware is more likely to include algorithms to find a balance between shutter speed and ISO levels which can significantly reduce digital noise.
Get a camera with a larger image sensor. When you are shopping for a camera, compare the image sensors of different cameras. More than megapixels, the image sensors will determine how well the camera can reduce digital noise.
Use a flash. If you must shoot in low-light, an LED flash will make it possible to keep low ISO settings to get the same illumination for your photo shoots.
Use photo editing software. Photoshop is especially useful for cleaning up pictures. Shoot in RAW format rather than JPEG. RAW pictures contain higher details and more information and they give better results after processing them with the software to reduce the digital noise in the captured images.