First of all, you need to determine the resolution of your camera, and the resolution modes available to you to take pictures. Digital cameras use pixels to store digital images. Increase in the number of pixel increase the quality of the image. That is the reason you will see different megapixel values for different digital cameras.
If you take the picture with high resolution, the quality, as well as the size of the image file will also increase. The opposite will happen if you take pictures with low resolution settings.
You can also experiment with different ISO options. You can use the ISO button present on your camera to adjust the sensitivity of your camera lens. If you are taking pictures in bright light, then you should adjust the ISO setting to its lowest value.
Set the ISO settings to higher values when taking darker images. Many cameras also come with automatic ISO feature that automatically adjust the ISO settings according to the light entering the camera lens.
Try adjusting shutter speed for different types of scenes. For instance, if you are taking a picture of still image, then you can try adjusting the shutter speed to slow, as this will capture more details of the objects present in the frame. On the other hand, when you want to take pictures of fast moving objects, then you will have to use fast shutter speed, or else, you will end up having a blur image.
You can also check for mode selection button on your camera, and experiment with different modes available, such as portrait, landscape, close-up shots, panorama, and many others.
Try adjusting brightness and contrast for different pictures, and you can also take pictures in black and white, sepia or negative modes.