Make one row understandable
Before importing a file, decide what each row represents. Is it a product, a variant or a supplier reference? Choose a stable identifier and check for duplicates. A recognizable product name helps your team work, but it should not be the only way to match records when that name changes later.
Give every column a purpose
List the fields you want to keep: name, SKU, material, dimensions and any other relevant attributes. Agree on units and separate values that need separate treatment. A combined field such as “green, cotton, large” looks convenient in a spreadsheet but makes later filtering and reuse harder. Keep the original file available so you can explain where a value came from.
Test a representative selection
Import a small selection containing an ordinary product, a variant and a product with missing information. Check the mapped columns, language and images before expanding the import. Correct the structure first instead of manually repairing many similar records. A successful import is not merely a completed upload: the products should also be understandable to the next person who opens them.