I first blurred the background to attract the attention to the couple.
I then selectively, using the adjustment brush, changed the skin tones using tint and color temp sliders. Then using a different adjustment brush using the saturation and color temp sliders adjusted his jacket and tie. Using again another adjustment brush with saturation and color I adjusted the candles and flower color.
Then adjusted the contrast and clarity globally. I did not want to smooth their skin to give the photo that old photo feel, but you could if you wanted.