5 minutes (plus paint drying time, optional)
1) Raise jack a little less than half-way.
2) Fold handle over top of jack. Line up the hole on the handle with the left-most screw hole on the floor.
3) Position Jack, as shown below:
4) Replace spare tire as shown below:
5) Optionally, remove spare wheel once you've made sure everything fits properly. completely remove spare tire well cover, and spray paint over the jack, leaving an outline of the jack on your floor for next time you use it. Paint may be bright flourescent, or any color that clashes well with the floor of the well. Don't spray too much, just enough to leave an outline. Let dry at least 6 hours (preferably with windows and trunk/hatch open) before replacing the tire and cover.
6) Replace retaining screw assembly as shown below: