What's an effective AI prompt for writing size/fit guidance copy for apparel listings

The Prompt

Write size/fit guidance for [product — e.g., a fitted t-shirt, wide-leg jeans].

Actual fit data: [runs true to size / runs small / specific measurements, model's size worn in photos]
Common fit questions for this product type: [e.g., "does it shrink," "true to size for broad shoulders"]

Be specific and directive ("if you're between sizes, size up") rather than vague ("fits true to size, please check our size chart").

Why This Prompt Works

Apparel is the single highest-return retail category, and a large share of those returns are fit-related — specific, directive guidance (“if between sizes, size up”) measurably reduces size-related returns compared to a generic “check our size chart” deflection that doesn’t actually resolve the shopper’s uncertainty.

How to Customize It

Supply the real fit data (does it run small, what size did the model wear) rather than letting the model guess — inaccurate fit guidance increases returns rather than reducing them. If the product comes in multiple fabrics or cuts that fit differently, write separate guidance for each rather than one generic paragraph covering the whole product line.

Common Mistakes to Avoid

Don’t default to vague boilerplate (“fits true to size”) if it isn’t actually true for that specific cut — that’s the exact gap that drives fit-related returns in the first place. Also avoid burying the fit note below the fold on the product page; shoppers who don’t see it won’t factor it in before ordering, which defeats the point.

Bottom Line

Specific, directive fit guidance grounded in real product data reduces returns in a way that generic “check the size chart” language never does.