Begin with your base. If it's dark or doesn't have a lot of contrast, duplicate it and set to Screen on Soft Light, on whatever opacity looks best. I didn't do anything to mine.
Fill a new layer with #c1d9e7, and set to Linear Burn at 60% opacity.
Fill a new layer with #9d837d, and set to Soft Light at 100% opacity.
Create a new Selective Color layer with these settings:
Reds: -100, 0, +100, 0
Whites: 0, 0, 0, -60
Neutrals: -10, -15, 0, 0
Blacks: 0, 0, 0, 20
Fill a new layer with #1a1300, and set to Exclusion at 50% opacity.
Fill a new layer with #1a0000, and set to Exclusion at 50% opacity.
Other icons made with this technique: