A card board packaging box will be offset printed and i want to make coloured variations to show the client a photorealistic mockup. What the client sees must be as close to printed thing as possible. Pantone colours will be used, but i dont know what technique i must apply to photoshop in order to see real colours when colouring with pantone. The surface i will colorise is just a photorealistic side of the box with shadows and highlights to give the impression of shadows. Problem is when must colour a layer i have no clue what layer setting must be applied. There are many to choose, overlay, color, hue, saturation, multiply, darken etc. Any ideas? Do i make any sense?