I love shooting in that fleetingly brief time when the sun drops from view and the ambient and artificial lights balance one another. This is the time to be experimental and try various combinations of shutter speeds and aperture. Many people might think that's it, the light has gone - the so called 'golden hour' has passed and it's time to go for an early evening drink. But just hold on a few seconds and magic things start to happen.
Shoot a lot more images than you might think necessary, judge manual exposures via live view in order that you can see what's happening and don't rule out trying things you've not tried before. The key to success is not being afraid to make mistakes and pictures that don't work. Try something, make mistakes and learn what works and what doesn't.
Some examples of images shot in the time beyond the golden hour.