This handy video shows some very simple ways to prepare vegetables - without chopping your fingers off in the process.
To slice: Place cut side down, and thinly slice from top to bottom
To chop: Place the tip of your knife on your board and rock back and forth.
To julienne: Thinly slice side to create a flat surface and prevent rolling. Turn the flat side down and thinly slice lengthways. Stack the slices an cut lengthways again.
To chiffonade: Stack leaves into a pile, roll them and thinly slice leaves crosswise, forming strips.