The process of coloring neat sketches is a significant activity while making animated movies or for better visualization in computer modelling. The color filling tools are widely available in almost all the image/video editing software, which will help us to pick a color from a color palette, and it can be filled on a selected region. This process is known as flat coloring. The flat coloring process is having a number of challenges. One of the major challenges is that the color may leak from the selected regions to other neighbouring regions if there are some small openings on the contours. The second concern while using flat coloring is that the whole selected regions will be completely filled the same color and hence the drawing will not have an artistic look. In this paper, we propose a new software application that will take a neat sketch as the input and the system will generate a colored drawing as the output. In the proposed scheme, we have converted the given sketch as grayscale or binary image, and we applied image dilation operation to fill the small open spaces in the contours (if any). Further, the closed regions are identified and colored with a predefined set of colors or with random color combinations. While coloring the regions, the proposed system will ensure that the adjacent regions will not colored with the same colors. A number of sketches have been considered during the experimental study and the results are validated manually.