What do you mean by "it"? For cartoon style a basic one color area is a starting point. You can add outline to it, set its width, add shadow to divide colors by 2 or 3 or more. You can add gradient/soft/area shadow to it. There are more variations. There are also many ways and tools to achieve it. You can draw it from scratch in bitmap (photoshop), vector (illustrator) or 3D software using shapes, fills, outlines, strokes, toon shaders etc. The easiest way to recreate picture you've added is to draw a rectangle with solid color, set black outline, duplicate, change solid colors and it's done.