Several years ago I had some shoelaces that loosened and untied themselves continuously. I didn't have enough laces to double knot the bow or do something like link shows. After some tinkering, I found a method that's very simple and worked very well.
(description is for a right hander) Just like a regular shoelace bow, you start off with the first loop of the bow in your left hand and, with your right hand, make a single wrap and pull the loop through. Instead of making the single wrap around the first loop, make two wraps and pull it through like normal. When you pull the bow, it looks exactly like the finished knot in the picture on the link.
It doesn't take any longer to tie or the dexterity of trying to fish the bow loops through another loop. It also works well when you don't have an excess of shoelaces to tie. The only word of caution is when you pull the loose ends to untie your shoes. Just make sure the free ends have not run back through the bow before you pull or you'll make a very secure, hard to pick out real knot.
