As Scorpio says, I've been doing this for 20+ years so I learned a trick or two but basically for aircraft you find a drawing then pixel reduce it to the wingspan you want.
That gives a rough starting point [A] then it gets cleaned up a bit [b] then the outline is applied over a blank fuselage with wing detail ( I have various version for single and muliti engine aircraft along with a series of engines configurations and that gets you to [C] ( more or less ) then it's adjusted a bit more [D] then the glass and prop details are added [E]
Then you create copies [F] using the various palette shades and picking the ones that give these results is part of that 20+ years experience and how many are done depends on how many you need.
Since all the copies are exact duplicates you can start with a base [G] then cut out one of the copies [H] then paste it to the base [i] . A more complicated one may require three or more cut outs [J]
The trick is to have good colour definition but keeping the contrasts reasonable otherwise its a mess of contrasting colours that obscure the detail in the actual aircraft or vehicle
These examples are sharp edge camo. The blended overspray versions are handled differently depending on the size and colour of the Icon. Sometimes it works......sometimes it doesn't
These have all been expanded 2x normal
