The word comes from the standard practices of the celebrity Charlie Sheen. His ability to convince himself that the downward spiral of his life is living life well, and his attempt to make others believe that the downward movement of his life is really a good thing is the inspiration of the word.
“I failed my test so I’ll have to sheen the whole episode when I tell my parents.”
"His life is a mess, but he's sheened it well."
How does one actually go about “sheening”? There are very particular strategies. Here is one a person can employ:
Person A: “do you really think it was wise to smoke that 7 grams of crack?”
Person B: exemplifying the perfect sheening strategy in the following reply: “Duh, winning.”
I can't believe John treated us all to dinner that is so sheen.
That's a sheen pair of shoes you have there.