If you want to balance all three exposure factors (aperture, shutter speed and ISO value) then Manual (M) mode is worth exploring.
Even in Manual mode your EOS will suggest the exposure. The exposure compensation scale (visible in the viewfinder) becomes an exposure meter. When the exposure level mark is in the centre of the scale, the camera is set for an exposure it considers correct.
Standard exposure index
Exposure level mark
This means, for example, you can set the aperture (using the Quick Control Dial) and shutter speed (using the Main Dial) for the effect you want to create and then adjust the ISO value to bring the index mark to the centre of the scale. In fact you can set any two of the exposure values and then adjust the third to centre the index mark. You can even choose your own exposure level but with knowledge of what your camera would select.
Alternatively you can select Auto ISO. This setting is especially useful when you want a particular combination of shutter speed and aperture to achieve a specific result.
Now you have read about how the components that make up exposure on your camera can change your photos, pick up your EOS and start taking photos using your new knowledge. Next month's Gallery will feature photos that have demonstrated the most interesting choice of aperture, shutter speed and ISO value. View this month's Gallery for more inspiration.