STEP ONE: Get a base - crop, resize, blur, sharpen, do whatever to make it workable.
Then duplicate the base and set it to Screen 67%. (wriggle it around to see what works better)
STEP TWO: Make a colour balance layer:
Midtones: 0, 0, 100
STEP THREE: This is my secret <3
Make a new channel mixer layer:
Output channel: Red
r:164
g:-69
b:0
Output channel: Green
Keep everything the default
Output channel: Blue
r:-60
g:60
b:89
Isn't it pretty?

STEP FOUR: Optional decoration.