Step one- your base.
Take your base, resize it, and place it on a blank 100x100 canvas.
(I got my picture from Veritaserum, in case you were wondering)
I sharpened my base just a little, but it isn't needed.

example.

Step two- curves layer. 
We need to brighten up our base, so we'll use a curves layer.
Go to Layer-New Adjustment Layer-Curves. 

RGB: 
Point One- 28, 46
Point Two- 74, 115

example.

Step two- more curves. 
Make another new Curves Layer.

Red:
Point one- 87, 94

Green: 
Point one- 85, 109

Blue:
Point one- 134, 90

example. 

Step three- color fill layer.
Much easier than those rotten curves. 
Go to Layer-New Fill Layer-Solid Color. 

Fill with #FF1301. Set to Soft Light, 25%. 

example.

Step four- selective color.
Go to Layer-New Adjustment Layer- Selective Color.

Reds-
Cyan: -100 | Magenta: 0 | Yellow: 59 | Black: 29

Yellows-
Cyan: -55 | Magenta: 0 | Yellow: 6 | Black: 0

Greens-
Cyan: 49 | Magenta: -68 | Yellow: 72 | Black: 19

Neuterals-
Cyan: 15 | Magenta: -4 | Yellow: -5 | Black: 0

example. 

Step five- more curves.
Make a new Curves layer.

 
Red:
Point one- 102, 108

Green: 
Point one- 106, 106

Blue:
Point one- 128, 150

example. 

And you're finished, if you like. =) 

Or, you can go on to the next step...

Step six- more selective coloring.
Make a new Selective Color layer. 

Reds-
Cyan: -77 | Magenta: 0 | Yellow: 54 | Black: 0

Yellows-
Cyan: -61 | Magenta: -16 | Yellow: -43 | Black: 0

Neuterals-
Cyan: 23 | Magenta: -3 | Yellow: -28 | Black: 7

example. 

Step seven: hue/saturation.
Go to Layer-New Adjustment Layer-Hue/Saturation.

Saturation- 15

example. 

Finished!

Remember that the coloring won't work on all icons, so try and play
around with the settings for best results. =)

psd. for the first icon.
psd. for the second icon. 

Please comment if you take the psd. files. ^^;
I'd love to see your results. =)

Also, let me know if anything was confusing. (especially regarding the
curves steps-- I'm terrible at describing curves. -_-)