We're going in January & I'm already packing.
I keep a large rubbermaid tub in the corner of my bedroom & anytime I come across anything I might need for the trip, that we don't need now, it goes in there...like travel size toothpaste, deodorant, extra swim goggles, disposable cameras for the kids, hats, flip flops, our coupons to redeem for free pins, etc.