With a mandoline you will have perfectly cut fries, elegant matchstick carrots and julienned zucchini. If you are making a potato gratin, you will be assured of even cooking when that mandoline cuts uniform potato slices. Garnishes will look professional, and if you like to stir-fry, those matchstick slices will cook rapidly.
An instrument that can work with such perfection is one of extreme sharpness and demands that you give heed to its blades. Be sure your work surface is comfortable - no reaching too high or too low. A hand guard comes with the mandoline. Use it. Primarily you need the guard when you are reaching the end of slicing and are holding a small piece of food in your hand. From experience we can tell you that it is easy to wait too long to pick up the hand guard. Please do not wait as this is not like a mildly scraped knuckle that you can get from a grater. The mandoline has a very sharp blade. We used ours all the time as we adjusted to it, even when it didn't appear that we needed it.
Then smoothly and fluidly, gently rock the food back and forth across the mandoline blade. Fall into the rhythm - it's a pleasant motion. And the key word is gentle - do not press hard, as the mandoline will do the work.
There are many varieties of the mandoline. A professional quality one can be purchased in a wide range of prices. Many have a dial to select the thickness of the slices you prefer. Handles protect the hand and help you grip.
You can also find less expensive ones that look like a grater and need to be hand held. These mandolines work as effectively as the more expensive, but require a little more vigilance.