You get this naturally over time if you just wait around in the Toy Box Hub, but to speed it up you can complete the tutorials given to you by the Hub hosts, completing all of one set of tutorials will earn you one present.
They spawn randomly all over the map, and finding them can prove problematic - best to use a character that can fly (alternatively, get the helicopter from the vehicle tutorial host) and have a look at the rooves of the various buildings, as my last few all bunched together on high buildings.
Simply walking or flying into the presents 'earns' it for you.