A structure is a configuration. An unorganized pile is a structure. So is a table of contents or a house of cards. Every thing has a structure.
To choose a good structure for what you are making, you need to find one that:
There will always be several structures you can use.
Allowing your content to try on a structure you believe to be bad or wrong can be helpful. When we determine what something won’t be, we often reveal a little more about what it will be.
Don’t settle for the first structure you come up with. Take the same things and arrange them, not in one way, but in two or three ways. Compare them. Iterate. Test. Refine. Combine. Change. Argue.