I want to sell articles of clothing but it is possible that the individual doesn't have money on them. Can I put down their information and have them sign to where they can walk away with the article of clothing and pay me later?
The document is called an invoice and the customer has taken the clothing “on account”. Most businesses of any size outside the retail sector operate this way.
Remember that you are effectively lending your customer money. What are the terms of this loan? What are you going to do when/if they don’t pay? You need to deal with this either in your sale contract or a separate credit contract.