Well i'm a tourguide in Central America and I do a lot of Jungle hikes with my guests. Ok 3 day sounds great, but it really depends on where you will be hiking, what type of enviornment you will be operating in is there water in the area, is it near enough that you will be able to access food when needed? will it be a moderate or extreme outing footwear will depends on that. will you be hiking with a friend or friends?  What if you or your friend or friends happen to get hurt ie cuts, puncture, scrapes ect.First Aid Kit also think about the bugs. Bug spray   What about your hygiene kit, protective gears,  cellphone, small radio, pen and paper in a dry bag, sleeping gears including tent and any special or prescribe medication. And don't forget your camera for those adventurous moments. Hey hope this help ... wish you a fun and safe adventurous hiking.