I wouldn't treat a romantic scene any differently than any other scene. I would really say the biggest preparation was chewing gum and breath mints! For a kissing scene it's all about the breath mints!
The wedding ring on my left hand was bought by my grandfather Samuel Miliband in Brussels in 1920. I never knew him as he died when I was one. But his ring was kept by my aunt until it was placed on my finger by my wife Louise 32 years later.