The secret to sunset photos is to underexpose your image. By underexposing your image you can get the strong colours to give you a really amazing image
Setting up your camera. First set the camera to aperture priority mode, then chose the aperture you want and the camera will select the matching shutter speed. e.g. try aperture F5.6 and take the shot. Then look at your shutter speed, because you were in aperture priority mode that camera auto selected the shutter speed. Now change your camera over to manual mode put in the same aperture and set the shutter speed to double the value the camera auto chose for the previous shoot previous shutter. Take another photo and the results should be a image with more stronger colours.
One of the most important things to know when taking photos in Aperture..
The smaller the F number the bigger the hole that lets light into your camera sensor. So the larger the F number the small the hole which results in less light getting into your camera.
A small F number means that you can take very fast photos, but you have a very short dept of field. Good for Portrait photography, digiscoping where you want to focus on a specific subject.
What is Aperture Priority? Effect on Shutter Speed, Depth of Field and Digiscoping