You protect it or make it indestructible with whatever tools you want, but equipment like Darksteel Plate works best because you can move indestructible off it as needed
It lets you look at the top three cards of your deck, attach any energy to your Pokemon, and discard the rest
In addition, the bottom of the card will have a textbox reading " TEST CARD - Not for constructed play ." The art is also often of lower, sillier quality as it is done in-house by R&D members rather than commissioned artists (hence the lack of artist credit on the cards)
And I also know one sold for 12.5k on a PWCC auction in the Summer of this year, but not sure anymore whether it was paid for (it probably was, though)
Discard the top card of your opponent's deck
Her card here represents all of this well