Use daylight, not your flash
Stand near a window in the morning or late afternoon, with the light coming from the side. Turn off the flash: it flattens colours and adds glare. If the sun is harsh, hang a thin white curtain or sheet to soften it.
Or let us make the mockup
Turn one plain photo into a polished product mockup, straight from the product page or your Files: your product on a clean background, worn by a model or in use, ready for your store. Pick Gemini or OpenAI to make it, and add a few words on the look you want. Start with a clear, well-lit photo, and the mockup comes out better.
Keep the background plain
A white wall, a sheet of cardboard or a plain bedsheet works. A busy background pulls the eye away from what you're selling. Use the same background for every product so your store looks tidy in the grid.
Take more than one angle
Your cover photo should show the whole product, straight on. Then add the back, the sides, a close-up of the fabric, stitching or label, and one photo of it in use: worn, held or on a table. You can add up to ten photos to each product.
Edit lightly
Crop to a square, straighten the photo and brighten it a little. Don't use filters that change the colour: a buyer who receives a different shade than the photo will ask for a refund.