Tutorial #15 - Subtle Gradients - PSCS2 - Translatable
Go from this to 
01. Take your pic and crop it to 100x100 pixels, then go to Filter > Sharpen >> Unsharp mask... Settings: Amount - 50%, Radius - 2 pixels, Threshold - 5 levels, click OK.
02. This step may not be required or may need to be repeated, it solely depends on your pic, I recomend doing it and then going back later and adjusting... go to Image > Adjustments >> Curves... Settings:
RGB channel
Point 1: input - 46, putput - 94
Point 2: input - 111, output 202
Click OK.
03. Layer > New adjustment layer >> Gradient map... select the black and white gradient (see image below if you don't know how to select the gradient) and click OK.
04a. For those of you who have access to an selective color feature:
Layer > New adjustment layer >> Selective color...
Settings:
Whites: C - 0,M - 0,Y - 0, B - -48
Neutrals:C - 0, M - 0, Y - 0, B - +27
Blacks: C - 0, M - 0, Y - 0, B - +100
Click OK.
04b. Or if you don't have Selective color:
Layer > New adjustment layer >> Brightness/contrast...
Settings:
Brightness: -23
Contrast: +36
Click OK.
05. Take this gradient, I think it was made by
colorfilter 
paste it on top of all your other layers and set to Screen at 100%.
06. Duplicate your base drag to the top of all your other layers and set to Soft Light at 100%
07. Duplicate the Soft Light layer.
08. Image > Layer >> New layer... grab a tiny text brush, mine is from
ownthesunshine, set it to #000000 and place it somewhere that looks good on your icon.
And you're done!
Other icons made with this technique:
...
01. Take your pic and crop it to 100x100 pixels, then go to Filter > Sharpen >> Unsharp mask... Settings: Amount - 50%, Radius - 2 pixels, Threshold - 5 levels, click OK.
02. This step may not be required or may need to be repeated, it solely depends on your pic, I recomend doing it and then going back later and adjusting... go to Image > Adjustments >> Curves... Settings:
RGB channel
Point 1: input - 46, putput - 94
Point 2: input - 111, output 202
Click OK.
03. Layer > New adjustment layer >> Gradient map... select the black and white gradient (see image below if you don't know how to select the gradient) and click OK.
04a. For those of you who have access to an selective color feature:
Layer > New adjustment layer >> Selective color...
Settings:
Whites: C - 0,M - 0,Y - 0, B - -48
Neutrals:C - 0, M - 0, Y - 0, B - +27
Blacks: C - 0, M - 0, Y - 0, B - +100
Click OK.
04b. Or if you don't have Selective color:
Layer > New adjustment layer >> Brightness/contrast...
Settings:
Brightness: -23
Contrast: +36
Click OK.
05. Take this gradient, I think it was made by
colorfilter 06. Duplicate your base drag to the top of all your other layers and set to Soft Light at 100%
07. Duplicate the Soft Light layer.
08. Image > Layer >> New layer... grab a tiny text brush, mine is from
ownthesunshine, set it to #000000 and place it somewhere that looks good on your icon.And you're done!
Other icons made with this technique: