@bananahmartin A few tips...
Take more photos than just front/back of an item. If it's a top take close-ups to show any pilling, especially along the side/underarm area. If it's pants take a closeup of the hem if there's any discoloration.
Describe any flaws, fading, pilling, etc in detail. Don't just say "good condition" and leave it at that. If there's a tear in the seam or a spot try to fix it before listing and make sure it's still worth listing.
Take measurements - lots of them!
If an item has been altered or hemmed make a note of it. If an item has shrunk in the wash make a note of it.