Where do I send an item I sold on ebay?

Where do I send an item I sold on ebay?
So, I got the package all wrapped up with the order receipt and barcode number and all that junk. Now, where do I send it? Do I send it in a post office?”
Can I just put it in a mailbox>?

Best answer:

If you’re in the US: take it to your post office, wait in line, hand the package to the worker, they will weight it and tell you the cost to ship it, and finally you pay for shipping. That’s it!