It's an over-generalisation, but in my experience men to under-think the packing issue for trips. If you read women's discussion threads about travel preparation, you will often note that they start planning, getting advice, shopping and packing far in advance of the trip. Men wake up 2 hours before their flight, grab the clean stuff, shove it in a suitcase and hope for the best.

If you're leaving on Sunday, spend some time today (Friday) assembling the relevant stuff, checking that it's clean and in good repair, evaluating each item's usefulness, packing everything (and I mean absolutely everything you will be taking), and then trying to move the suitcase. Watch out in particular for heavy shoes (especially those that only go with one or a few wardrobe items); light colours (get dirty easy), clothes that only look nice when just cleaned/just put on (e.g. crisp black, linen trousers will look rumply and linty quickly); clothes that are hard or expensive to clean (e.g. dry-clean only); heavy/bulky clothing (e.g. more than one pair of jeans, heavy cotton sweater instead of lightweight polar fleece); and separates (shirts, jackets or trousers) that only work with one or a few items in your wardrobe. It probably will be quite humid, so you'll want to have enough lightweight shirts that you can go through at least 2 per day for 5 days, unless you've got very easy access to laundry. And while you're at it, pack an extra stick of deodorant.

You might have limited access to the internet, so you might want to buy a portable storage device or two and download relevant files and email addresses, including travel e-tickets, hotel bookings, etc.