Build your new city: you can add streets, grass, buildings, means of transport, bridges, animals and persons. Also plantations, traffic signs, etc. And you can apply different color paterns to different parts of an item.
When you click an item it will be added to the city; then you can drag and drop it to the place where you want to put it. You can modify the item with the toolbar that is visible next to it (there's tools to rotate, hide or move items back and forth, to draw over them, change their color patterns, erase them); there's also available options in the main toolbar: to draw on the city, to modify the weather or other general parameters, and to print the final image. To apply a color pattern partially on an object, start by choosing the part to be colored and then click the color pattern you want. You can repeat the process for different parts of the object. The little menu for the color patterns allows you to customize colors, shapes and dimensions, among others. In general, you have to click or drag and drop to place, move and modify items in the scene; a task bar is visible at the bottom if you move the mouse pointer to the bottom right corner of the game.