I calculated the red channel, desaturated the original image and overlayed the new "red" image blurred. It's a kind of infrared trick I learned a while ago. The blurred image over the original gives it that soft aura I really like.
Then,
This one is a little bit more extreme. I used curves exclusively to increase the exposure and then play with the red and green tones to get a sort of retro-vintage look. Then I added a vignette.