The best piece of advice is PLAN AHEAD. This is a very large, very remote piece of the world. Airports are few and very far between. Fuel is something you want to call ahead and pre-arrange to ensure it's available. Take along a good survival kit, including LOTS of bug juice. Temperatures range from hot and humid to below freezing... in the summer! Be prepared to spend several days in a tiny town where there is nothing to do, for several days, while you wait out weather.
All of this sounds pretty negative, so now for the positive. Be prepared to see some of the most incredible untouched territory on earth. Flying over this land gives you a sense of just how small, fragile and unimportant we are as humans.