For online sales choose a combed cotton single jersey of 180–200 GSM: it is opaque, drapes well and does not look thin in photos. Customers return products that shrink, twist or turn see-through, so ask for a fabric with low shrinkage and good stability. A tee that is too thin gets bad reviews; a very heavy one does not suit everyone. State the weight and composition clearly on the product page. Do a wash test before launch to confirm that size and shape hold.
How do I choose the weight for unisex tees sold online to get as few returns as possible?

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Printing & decorationWhich printing method for small runs: DTF or screen printing?
For small runs, below roughly 50–100 pieces, DTF is usually more practical: it needs no screens, accepts multicolour designs and gradients, and can be ordered per…
Printing & decorationWhich is better, DTF or DTG?
It depends on fabric and volume.
Printing & decorationShould knit fabric be washed before printing?
For most print methods washing is not required, but the fabric must be dimensionally stable and dry.