You've probably heard a lot about the drone registration. Basically the FAA now requires everyone who buys a drone that is over .55 pounds to register it with them. They charge a 5$ fee however if you register it before a certain time then they will refund it.
So what happens if you don't register it?
Well they certainly aren't playing around with the consequences. Apparently you can get up to 27,000$ in drone fines. Also you can end up spending up to 3 years in jail for failing to do this.
How can you register it?
You can just simply register your drone through there website. Simple go here: http://www.faa.gov/uas/registration/ and just register it. It doesn't really take a lot of your time so i recommend to do it as soon as you get the chance. It can save you a lot of headaches in the future.
What happens after registering?
The FAA gives you a registration number. You need to keep this registration number on you at all times. If you are ever questioned they will ask you about it. Preferably keep it as a sticker on your drone.