Hey everyone!

If you want to make your map look like it has a different shape than the square plot of land you are usually stuck with, you can paint your tiles in the color of the void surrounding the map! Typically, this was often done by using a custom object, which was then placed on all the tiles that had to be colored black. In more recent times however, a lot of people have started using palettes for this! Simply change your palette to replace purple with the void color, and you can then use the purple grid land texture to paint your land black! 

The good thing about using this method is that it's very easy to paint large areas of land black! It also will not use up any object slots and will not count towards the object limit in your park. The downsides are that it might look a bit funky when it starts to rain in your park, and that you will have to sacrifice a color in your palette to make this work!