Colloid crystals have been utilized in a wide range of fields because of their well-controlled structure and functionality. Various preparation methods have been developed so far, but most of the methods could not be applied to the colloid particles with their size on the order of microns. Here a facile preparation method is demonstrated, by utilizing an intentionally generated convection flow in a droplet of suspension by simple heating. This method is quite versatile for various surface types and a wide range of particle size (200 nm-6.0 mu m). Furthermore, the film thickness could be easily controlled by the concentration of the colloid suspension.