This instructable covers basic wood whittling technique. You will learn a little bit about tools, wood, technique, and safety. Hopefully it will be enough to get you interested in learning!
Wood carving is not something you pick up over night; it requires a lot of patience and practice. What you will find, however, is that as you practice you will develop intuition that will allow you to tackle increasingly difficult problems on your own. It's an enjoyable and relaxing activity that I would recommend to anyone interested in learning a new skill.
Step 1: Tools
Let's start with tools;
You're going to need a knife. While you could conceivably use any kind of sharp knife, I highly recommend investing in something nice... I use the chip carving knife pictured here. High quality tools are going to be hand-made with tempered steel that will cut better and last longer than the low quality stuff. There are chip carving knives with different shapes that will make difficult cuts a little easier, although they aren't necessary for the beginner.
You'll be putting your knife/knives through a lot of stress and thus you will need to sharpen them. You can buy sharpening stones or you can use a combination of 600+ grit sandpaper and water or oil. Any piece of leather will work as a strop. I won't get into sharpening in this instructable, however there are plenty of resources out there for you to learn.