Adopt the FIRM standard if one exists — consistency beats cleverness. Absent one:
ProjectNo_Deliverable_YYYYMMDD_vX_INITIALS.ext · never “final” in a filename (there is no final, only v-next) · _RAW data immutable · _ARCHIVE for superseded versions same-day.
Folder skeleton: 01_Admin(scope,contract) · 02_Data_RAW · 03_Analysis(models,calcs) · 04_GIS_CAD · 05_Deliverables(by version) · 06_Correspondence · 07_Reference — scriptable (Starter Automation Projects #5).
Backups: know where the firm’s live/backup copies are; local-only work product is a resignation letter you haven’t sent yet.
Excel/model version control: change-log tab; who/when/what per version; models emailed out get frozen copies in 05.