Short answer
Care for overcoats depends on the chosen cloth and its care label. Ask the tailor for instructions for the exact garment; follow the label and avoid heat or cleaning methods it does not permit.
Overcoats live on shaped hangers between wearings, brushed and aired; a season-end clean before storage keeps them for decades.
Follow the care label for the chosen cloth and ask the tailor if the instructions are unclear. Storage, ironing, steaming and cleaning advice can vary by fibre and finish.
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