Hi Johnboy, The amount of care and cleaning your knife will need is dependeant on a number of factors. Firstly, a carbon steel blade will need a little more looking after than a stainless blade as it will be more prone to rusting if left damp and more prone to staining by various chemicals in both the things you cut and the grease/moisture from your hands. Many folks are happy to have their carbon blades build up a patina from use whilst others like to keep them all silver shiny. The latter takes more cleaning, but the patina can actually help to protect the blade a little as well as making the knife look like something you use rather than a collectors piece.
Generally it's a good idea to keep your blade clean by wiping it with a cloth after every time you use it. This keeps both the blade clean and prevents grit and muck getting transferred into the sheath (from where it can a sod to get rid of it ) Carbon steel blades will benefit from a very thin coat of oil if being stored but beware of using oils that are harmful if you intend using the knife for foodstuff or for making items that will be used for food. Some folks like to use a little olive oil, vegatable oil, or nut oil on their blades for this reason.
Stainless blades require less maintenance, but remember that they stainless not stain proof.
Keep your knife sharp. There are few tools as dangerous as a blunt knife. Sharp blades cut without too much effort and the edge "sticks" to the workpiece. A blunt knife will be far more likely to slip from the work, and sods law dictates that when this happens the blade will find a way to discover some flesh in it's path before you can stop it. Blunt knives require more force to work with making slips even more likely as well as being more likely to split or break the item you are making.
There is more to keeping your knife sharp than knowing how to sharpen it too. Carrying the tools to sharpen your knife whilst out and about is a good idea as wear and tear in the field will dull the edge a little and the ability to "touch up" the edge without taking the knife home is invaluable. Never stick your knife in the ground. Grit and stones are not good things for knives! Cut small items, that cannot be held on their own, on some sort of block or board. a dead branch will do fine, better still the flat side of a split log so there is no chance of grit or stones that became embedded when the branch/log fell to the ground. Just dont use the ground as cutting board. Your knife goes through the work and into the ground, hits a stone and puts a nick in your carefully stropped edge...
Don't keep a knife in it's sheath for long term storage, especially a carbon steel bladed one. Better to keep the knife lightly oiled and wrapped in oil paper. A leather or plastic sheath can harbour enough moisture to make even a stainless blade rust if you you leave it in there for a week or two. Carbon blades can rust in a perfect representation of your fingerprint if you touch then witha clammy finger after cleaning, let alone if left in a wet sheath.
Use your knife as a knife, and ONLY as a knife. A knife is NOT a screwdriver, a pry-bar, a spade, a hammer or an anvil. Use your knife with care. Treat it with care, and it should last you for many many years.