Take notes. You won't be able to remember everything, so write stuff down. Whether you use a pad of paper, a tablet, your phone, a laptop or a recording device doesn't matter, but take notes.
Collect business cards. Connections are one of the most important things you will take from this event. Write clues on the cards such as why that person would be important to you - maybe they have a connection to that elusive unobtanium supply.
Technology. You need to carry technology, but don't get lost in it. Maybe just a tablet and a bluetooth for making calls. I bring a phone and a laptop. Some people tweet constantly, others find that a distraction from actually being there. You must find your path.
Comfortable shoes. You're gonna be on your feet a lot, and walking a good bit, so you need to be comfortable. Dan Staples seems convinvced I wear flip-flops, but it's not true. They're sandals. Sandals, I tell you. Comfortable ones. Anyway, dress comfortably. Running shoes are a great choice.
Backpack or shoulder bag. You need something to carry stuff in. If you already have a laptop bag, that's perfect. Vendors give out stuff you'll want to hold on to, plus you need a place to put those business cards.
Sensible food plan. When traveling, sometimes its easy to lose track of food. Either too much or too little or the wrong kinds. Grab water bottles whenever you can (and put them in your backpack). These events usually make it easy to manage food, but if you're talking to Imre Szucs or Ken Grundey or Sean Cresswell or Tushar and lose track of time and miss lunch, that can make things uncomfortable. Anyway, pay attention to food, because it affects your state of mind.
Casual encounters. Leave time to run into people in the hall or between sessions or at lunch. Connections between people are an important part of why this event is so crucial. Take time to talk to people you may not see until next year, Email is great, but there is nothing like talking to people face-to-face. Make sure you understand your priorities going in to this event and make your schedule flexible based on those priorities.