How do I watch the sunrise/sunset without damaging my eyes?

Me and my girlfriend are going on holiday in June to Greece. She told me one of the things she's always wanted to do was to watch the sunset on the beach. I responded with "That's bad for your eyes you know". Talk about a charmer. Any way I'm just wondering does it damage your eyes? I've never looked at the sun because I've read and heard so many things that tell you not to so I just avoid it. So yeah any advice would be great, thanks.