There are certain items that sell very well in pre-owned clothing which is how you want to list your item. Don't say used in your listing.
Distressed Levi jeans go very well. These are vintage Levis that have a worn look to them and can include fading, minor tearing in the knees and rear pockets.
If the rear waist tag still show Levis, that's even better.
High end names such as Cardin and others can fetch a nice price.
Old Navy and similar type clothing wont get much unless they are new and probably wont sell as well as,-- I forget the name but it was a cheap mail order company. Not Lands End.
Any type of outdoor sports wear in good condition like Columbia will sell good too.
Forget any kind of socks or underwear obviously unless in absolute brand new condtion and a sought after name.
Certain other items will sell as well such as old leather biker clothes.
I sold a Firemans chemical jacket for a nice penny but my guess is you don't have one of those.