An overnight kayak trip could be considered the water-bound backpacking trip. It's the same kind of concept except, rather than load up a backpack and hike your gear everywhere, you load up a kayak or canoe in the same way and paddle your gear everywhere! If you have gone backpacking before, you're already familiar with a lot of the concepts. If you haven't gone backpacking before or even taken a float trip, but want to eventually take an overnight float trip, then this is the place to start!
Picking a Boat
Like an appropriately sized backpack is to backpacking, an appropriately sized boat is equally important to an overnight float trip. Your two primary options are a kayak or a canoe. There is no wrong choice, however, you may want to consider the following before rushing to a decision.
Do you require space to haul a lot of gear?
Are you going to float with a buddy?
Are you able to handle a boat solo?
Depending on how you answer these questions, you will steer yourself towards the best pick in boats for your trip! If you intend to bring a lot of must-haves along, thus requiring lots of space, you might want to lean towards a canoe as they are generally open, deeper, and in most cases longer than a kayak making them perfect for hauling lots of gear. If you are going with a buddy and you would like to split the work of paddling and/or the cost of renting a boat should you need to rent one, a canoe might also be your pick as they tend to be built for 2 or more people while still offering plenty of space for gear. If you are going with a group but still intend to be on your own, a kayak is probably your choice. You can keep your own gear with you, handle your own boat, and, although it is not impossible, it is much harder to paddle a canoe on your own compared to a kayak.
Packing a Boat
If you've gone backpacking before, you can probably glaze over this part or skip it altogether. After all, you should know exactly what it takes to fit 60 liters of stuff into a 55 liter backpack. This is the same concept except the soft backpack is a rigid boat and you need to be extra worried about keeping things dry. For those who have no backpacking experience, it's time to learn the art of "essentializing" or bringing only what you need and maybe even less. Regardless of what boat you are using, you need the following items: food and water, clothing, and shelter. Everything else is largely non-essential. Food and water needed will vary by length of trip and whether you bring a water filtration system or not. Clothing, depending on what you see yourself doing on this float trip, will almost certainly be limited to sleepwear at night and swimwear during the day regardless of the number of days and nights on your trip. Your shelter, of course, will only ever be the one shelter you use on the trip. No sense in bringing more than 1 shelter, right? To really save on space, you could take a hammock as your sleeping shelter! Just hope it doesn't rain.
While we're on the topic of packing, you're going to want to pick up a few dry bags. Keep in mind that, although they come in many sizes and the same general shape, you need to make sure they fit in your boat and holding your gear. You might need several 10L bags rather than 1 large 30L dry bag if the 10L bags will fit in your boat while the 30L bag alone will not.
Loading a Boat
Like you would with your backpack while backpacking, you need to pay extra attention to load balance. Depending on the overall width of your boat, you might already be a bit unstable on the water and, with the extra weight, you could be spending your efforts fighting to stay upright more than paddling downstream if your load isn't balanced out just right. Consider placing your heavier items closer to the bottom of your boat. This will help keep you from being more top heavy than you already are. It's more than just putting things in the right place but making sure they don't move on you either. Water has a way of moving your boat around on you whether it's waves, riffles, rapids, or the loch Ness monster... This can cause your gear to shift if not properly secured which could put you, your boat, and all your gear in danger of capsizing.
Time to talk reality. You are traveling through water in a small boat with all your gear. It can be treacherous. Subsurface obstacles can possibly capsize your boat, storms could cause a dramatic rise in river levels at night leaving you stranded at your camp as your boat floats away, or you could face tremendous wind and waves if on a lake or the ocean. Although this is not always the case, you could be quite remote and hard to reach which tends to accompany a lack of phone signal. You should be prepared to help yourself in all cases and, if you are able to reach the outside world for help, provide reasonably good directions to finding you if you should be in need of assistance. Here are a few things you should do to be as prepared as you can be.
Draft an itinerary of your trip
Include time tables of start and stops
Include campsite locations, even backups if you find first picks to be inadequate
Include any day trip information if you should stay at a spot to explore a point of interest
Leave your plan with someone who knows what to do if you fail to check in or make it back at an appointed time!
Bring a GPS
You knowing where you are is the most important thing. How else will you be able to relay that information to rescue teams?
You may want to pack this in a bag and forget about it but you shouldn't! Keep it dry and attached to you in case you get separated from your boat or other gear!
Bring your phone
If you need to make a call, and can make a call, you'll be happy you brought it
Make sure you bring extra battery packs to keep it charged on lengthy trips
Keep it dry and attached to you in case you get separated from your boat or other gear!
Learn how to handle your boat
If you capsize, can you right your boat in open water with what you have available?
Consider taking canoe or kayak lessons before setting off especially if you haven't extensively used either boat before
Watch for wildlife
When you make it to land, watch out for raccoons, possum, and other rodents. They will destroy your gear to get to food or find nest building material
While you are in the water, watch out for snakes! Some of them may be venomous and will seriously ruin your trip if you are bit