The most important rule of thumb is to pack light. Most operators will provide you with per/angler weight restrictions and I strongly suggest you follow them as more than once I’ve seen pilots order folks to leave some of their gear on the dock. Weight is all about safety to a bush pilot. He simply isn’t about to sacrifice his safety for your weight! Some folks suggest that you pull together all the food and gear you think you’ll need, then leave half of it behind when you pack. I’ve learned over the years that you never wear all the clothes you think you will, nor will you consume all the food you thought you’d need. Notwithstanding that, be sure to pack quality raingear and some warm clothes, even in the heat of summer. As long as you can stay warm and dry, you can fish in just about any weather.
Similarly with your tackle – there’s little sense in lugging up your entire tackle box. Think about where you’ll be, what fish you’ll be targeting and pack only that which specifically meets your needs. One of the most valuable items I like to take is a portable fishfinder/GPS. Having one on hand can really shorten the learning curve on a new lake. It will also provide a measure of security against getting lost. Taking the time to properly prepare will seriously enhance your fishing adventure.