Holly

Presents only appear while the game thinks it is Christmas, and it decides that from your system calendar. Outside the window there is no farm and no substitute, so if you want a wreath on the wall in July you either stockpiled unopened presents last winter or you go without.

Open them in bulk and sort the pile afterward rather than unwrapping one at a time and getting distracted. The decorations come out often enough that a couple of stacks will furnish a whole base, and the same spree is what turns up the rare toys, so there is no reason to save any.