Animal Crossing New Horizons island design ideas can be based on what items you have. For instance, if you have a large number of certain ACNH items, you can consider to use it to decorate your whole island, if it's not suitable for decoration, it's also a good option to sell them exchange for Animal Crossing bells and purchase other items. Take a look at this ACNH island design, Mush Lamp in various colors are put on the island, which makes the night is bright. There are also colorful Star Fragment applied.