Minecraft wiki entry for Redstone_tips, associated text: This is a simple yet very effective tip, especially if you create redstone contraptions that have many different parts to them, such as comparator clocks mixed with other redstone items. It is best to use different colored wool, concrete, or terracotta for different parts of the circuit. If you place all of the redstone on top of the same block, for example, out of dirt, soon you may completely forget how your redstone works. Furthermore, this is important if you want to show off the redstone contraptions on YouTube, so people can copy your design in their Minecraft world or you want to be able to go back to your project and understand what parts of the circuit perform what function.