Import the model of your gift box into 123D Make
and use the "Panel" feature to deconstruct it into a series of, well, panels. You can choose what sort of joinery you want to use at all of the seams, but I recommend using "rivets" or "lace", both of which will leave a series of holes that can be used to tie the panels together.
While you're using this software you can select "View parts layout" at any time to see exactly what your final jigsaw puzzle of a gift box will look like. If it's looking intimidatingly complex, you can go back and simplify your model slightly. If you're happy with the results, then output it as an EPS vector file.