The consensus in this thread is that there are a lot of variables. I have a single PSD file with layer groups... some pictures I load up and try in all my preset groups and sometimes it simply doesn't work.
Generally I've found what mine all have in common is:
2) Hue/Saturation adjustment layer w/ Saturation at -25 to -40
3) Gradient Map adjustment layer. Experiment, but a dull orange to teal is a good starting point. Set transparency down somewhere between 5 and 20 and play w/ the type of layer (screen, overlay, etc.)
Then, you can mess aroudn w/ all sorts of other things.