Don't forget those who aren't fortunate enough to live a life of luxury. I don't mean "think about them a few seconds and go back to feasting and opening overpriced trinkets" I mean really think about them. All over the world, even in the US, there are people who are in desperate need of real help - the lucky ones of those are in shelters tonight with nobody to celebrate with and no money for needs let alone extras like presents.... the unlucky ones are living on the street.
When I say don't forget about them, the next time you say "I need" to something that isn't really a basic to your survival think about those not getting medical care or having a place to live because they fall through the (gaping holes) of the medical and aid systems. I was one of the lucky ones, someone helped me get some of the help I need after some years living homeless - there are many more that aren't. So the next time you see someone that is truly needy don't give them a scornful look, don't give them cash or worthless "advice" (often times they CANT get the help they need because of various disabilities)... offer them what you can... a hot meal, a shower at your home, some snacks you have sitting in your car, whatever you can spare. Maybe go to a shelter and ask how you can help - there's ways to donate food and other needs instead of yard saleing them or dumping them in the trash.
So yes, have a truly merry christmas by doing the most kindhearted thing you can - be selfless to someone who truly needs it.