While some sunsets will be a pleasant and unexpected surprise, to become an expert sunset photographer, you’re going to need to put some work in.
As a sunset photographer, it pays to always be on the lookout for great sunset viewing spots. As you go about your business, keep an eye out for potential photo capture points, making note of these locations and even taking snapshots on your smartphone for reference. Things to look out for include natural and manmade landmarks which can be viewed clearly from high vantage points, and clear and uncluttered spaces.
If you need help understanding the direction of the sun and when and where it will be setting, there are countless online resources available, including this one.