I sell a lot on vinted, cheap and cheerful, most stuff is £1-£2 apart from better brands. I take lots of pictures, so front/back/details like zips/ties/pockets etc/labels showing size and materials.
I describe it honestly, although I don't tend to sell stuff that is damaged anyway, but make sure that any flaws are shown in the photos.
You can offer discounts for bundles, so that people get a bit off for buying more items from you.
I only offer evri and inpost as postal options. Yodel is too far away to drop off to and Royal Mail is a pain as the buyer could underpay.
A lot of people will favourite things but never buy. A lot of people will offer a lower price but then not proceed even if you say yes.
I have made several hundred pounds over the past 3 years, selling clothes, books, toys, toiletries, house bits, makeup, jewellery, bags, shoes, GCSE books etc.
I have saved a fortune buying DD's Christmas and Birthday presents from vinted using the balance from my sales. I got some wonderful musical theatre books for £10 each instead of £35 brand new.
Good luck