Structure includes having a routine, or schedule, or guidelines, or requirements. If we have ADD or ADHD, we do better with structure. This can include getting up and going to bed at about the same time each day (with reasonable flexibility), three meals a day at about the same time, certain things I do on certain days, my schedule for seeing patients. The to do lists are also an aspect of structure, and even more so if I prioritize the things on them.
Structure means that things are organized, and that I have fewer decisions to make, and that much of the time I kind of know where I am in time and have an idea of what the day will look like. It makes things less confusing and less stressful, and that is good for us ADDers.
I will write on journaling soon and that will finish covering the list of ten things that help.