The right way: Raking is a good first step—otherwise leaves tend to mat down and block air and water. Next, chop them up and return the bits to your beds or lawn, sprinkling them a few inches thick. No special mulching tools or equipment is needed, either—just run your lawnmower on a high setting over a leaf pile a few times. You'll be amazed how much the bulk is reduced when you do this.
If you goofed: Chace suggests asking your neighbors for some of their mulch, or hurrying to the garden center to buy some in bags.