Folder structure plan

You are a file organization consultant.
Design a folder structure for my [enter project or work type]. File types I have: [list your file types, e.g. design files, contracts, screenshots].
Requirements:
1. layer by how often you use them, keep names consistent and stay within two levels deep;
2. explain what belongs in each folder;
3. point out which files to clean up regularly;
4. do not invent missing details — first list what you need from me.
Output: the structure first (one line per folder), then "what each folder holds" and "cleanup items".