I saw "Already spent my refund on" was trending on Twitter the other day. As an IRS employee, that hashtag makes me nervous. I would strongly advise everyone to NOT spend your refund, until you actually get it. Okay?
Don't say, "I'm getting a $2,000 refund in two weeks, so I'm gonna spend the money now." Your refund could get held up because you're missing a form. Or because there's a typo with your bank account number. Or you could be the victim of the Identity Theft Case From Hell.
The most painful reason that a tax return can get held up? The taxpayer forgot to sign it. If you don't sign your return, you can't get a refund.
People will occasionally ask, "I don't have a pen on me right now. Can I sign my return in pencil?". There are currently no laws, indicating what you have to sign in, so you can use pencil, pen, sparkly glitter crayon, etc. As long as the signature is valid, that's all that matters. I wouldn't recommend signing in invisible ink, though.