When I was pregnant with my first child I worked at a charity thrift store. I sorted shoes and clothes. People donated trash!
So here are some guidelines to donating:
1. Toss out trash. If it has mold, bodily fluid stains, holes, tears, or broken, throw it away. There are a few exceptions to broken items. If it's an antique, you can still donate it. Some places still accept holey shoes and clothes because they will repair them. Ask before you donate.
2. Clean items. It's the courteous thing to do. Most thrift stores do not clean items because of the large expense.
3. Donate with a giving heart.