1. Duplicate your base, set to screen, at whatever opacity suits your icon (Not too bright).
For mine, I chose 50%
2. Duplicate base and set to Soft light, once again, at whatever opacity suits your icon.
I chose 50% again.
3. New adjustment layer > Colour Balance.
Highlights: 20 / 0 / -10
Shadows: 0 / 0 / 10
4. New adjustment layer > Curves.
RGB: I: 42 O: 30
Red: I: 60 O: 33
Green: I: 33 O: 66
Blue: I: 19 O: 72
5. New raster layer with #ccf4ec. Set to burn 100%
6. New raster layer with #f5ebd3. Set to multiply 50%
7. Sharpen once if needed.
And you're done :) Would love it if you showed me what you got! I realised the tutorial is quite image heavy, and different bases can sometimes look completely different to this, but if you mess around with the opacities you'll get something that looks similar to this:
Others made using this tutorial: