NapkinLedger stores no files. Your paper needs one home.

Keep it boring and single: one shoebox per quarter, one phone album, one drive folder. One place, not two, or paper gets lost.

Point entries at it. Every form has Reference: write INV-24 or box Q2. Balance adds Small purchases folder reference: name the box for this month's small receipts, like Shoebox Q1.

Keep until tax deadline plus margin. Rule from 90/10: the box is proof, the gap stays small and explainable. Overflowing box means record more next month, not buy a bigger box.