Get an onion chopper from places like Bed Bath & Beyond. It's quick and will save you lots of tears!

         I am by no means a professional chef. I have no culinary training, but just my trial and error learning method of how to cut an onion. I start by halfing it so that it lays flat on the cutting board. Using a sharp knife, I slice the onion down so that the rings are in a half moon shape. Then I turn the onion and cut it down again, perpendicular to the previous slices. It cuts the onion into nice squares, and keeps everything pretty organized. A nice little trick is to keep a lit candle close by... helps cut down on the tears!