My friend is wanting this cake design and I have no idea how to even begin with airbrushing this. I’ve not done to much airbrush work. Any help or advice would be greatly appreciated. 
I don't know if I can explain this, but you need to use templates to block out the shapes, mountains (or whatever they are supposed to be) and the vertical lines. Torn paper works well because of the irregularity. There are probably videos on YouTube that can give you the idea.
Well the little bit I remember about that you will start w/ the lightest color all over Not sure how to make the design - basically just lines but they will be added later Then you’ll need to mask off the parts that will remain light spraying the v darker then the tops That’s how I’d approach it I sure would practice A LOT — probably on paper to get a good feel for it then spread some icing & practice on that as it probably will take the color a bit differently Remember when you are too close the color will run Too far & the color will spread all over the place so some how mask off those areas that need to remain light Hope other will add more details
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