Go from
this to
01. Take your base and crop it to your liking. Filter > Sharpen >> Unsharp Mask... settings: Amount - 50%, Radius - 2.0 Pixels, Threshold - 5 Levels. This is your base.
02. Duplicate the base and set to screen at 100%.
03. Duplicate the base again and drag to the top, set to screen at 100%.
04. Duplicate the base once again and drag to the top, set to Soft Light at 100%.
05. Layer > Merge Visable or Control + Shift + E
06. Layer > New Adjustment Layer >> Curves...
RGB Point One
Input - 61 Output - 0
RGB Point Two
Input - 243 Output - 253
Red Point One
Input - 49 Output - 0
Green Point One
Input - 29 Output - 0
Blue Point One
Input - 14 Output - 0
Blue point Two
Input - 220 Output - 237
07. Layer > Merge All or Control + Shift + E and you are done!
More icons made with the same technique:
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