The Order & Complexity Toolbox for Aesthetics (OCTA; Van Geert, Bossens, & Wagemans, 2023) is an open-source Python toolbox and point-and-click online application to create multi-element displays, with tools to manipulate regularity (order) and variety (complexity) along multiple element features (e.g., shape, size, color, orientation). OCTA also allows images, complex shapes, or dynamic feature changes (e.g., in color or orientation) to be included in the stimuli. By attending this tutorial, you will become familiar with both the basic and more advanced functionalities of OCTA. The tutorial will also introduce how these OCTA stimuli can be used in different types of online experiments.