to 
This is my first translatable tutorial. How exciting for me! I don't really have a good way of describing this coloring, only that it has a bit of a vintage photo look, but with vibrant colors.
First off, you'll want to crop your picture of course. I am using this photo of Xavier de Rosnay from the cobra snake. (If you can't tell, I'm a complete Justice fangirl! ^^)
After cropping:
The picture I was using was rather dark, and since I'll be using multiply and burn layers later, it's fairly important to use a screen layer or two (ie, duplicate the base and put it on screen). The number of layers and opacity will, of course, vary with your base. I just used one on 100%. If your base seems to be desaturated or washed-out looking, I'd also reccommend a soft light layer.
So now it looks like this:
Next, I wanted to get a bit of a faded look, so I put on a layer of #F5EBCD on Multiply at 47%.
To make sure the red tones weren't completely overtaking the blue tones, I added a layer of #E4FDFF on Color Burn, 100%.
To add to the 'vintage' feel, I added the classic dark blue exclusion layer, which will soften out the lightest and darkest tones in the base a little. Mine is #06122A, Exclusion, 34%.
I still felt that it looked too light, though. And now the blue tones were starting to come out too much, so I added a layer of #C69C1B on Color Burn, 21%.
Now for the vibrant colors that I like so much. I originally used Selective Coloring, but I wanted to show that it can be done with Hue/Saturation! It just requires thinking about it a little differently.
My Hue/Saturation layer looks like this:
HUE SATURATION LIGHT
MASTER -1 +20 0
REDS 0 +12 0
YELLOWS 0 -24 +6
GREENS 0 0 0
CYANS -1 +16 -9
BLUES 0 0 0
MAGENTAS 0 0 0
(If you're looking for Hue/Saturation in Photoshop, it's Layer>New Adjustment Layer>Hue/Saturation.)
Of course, depending on your picture, you'll want to change it slightly, but the basic idea is to bring out the reds and cyans, as well as generally adding color to the base. The more saturation you add, the brighter that color will look. I like bases with color elements that stand out, like Xavier's bright blue headphones here. If you have anything like that in your base (and it's not red or cyan) you can turn up the saturation on whatever color it is to make it pop out.
So I ended up with my icon looking like this:
Other icons made with this tutorial:
