First, make a list of what you need or may need. You can pack the last day but make sure you have everything. Check weather.com to see what is going on and pack accordingly. Take sunblock, medications(prescr. if any as well as for cold, pain, tommy and so on), Remember everything costs much more in Disney, so it is better to be prepared. do not forget Purel. Also make sure no liquids and sharp objects goes into carry on bag, it belongs in your check in. Have fun.
depends on who you are packing for. If you are just packing for yourself you can start 1-2 days before the day of your flight. If you are packing for three kids then I would start 5-7 days before to keep it organized. hope this helped :)
If it were me, I would have started packing already, but that s because I take too much stuff. lol. Don t forget sunscreen a light rain jacket. Other than that, you ll need your toiletries, clothes, camera, you re set to go. Have Fun!