I actually have taken to tying them slightly differently than in my on line tutorial (and one of the projects I hope to get to soon is to make a "how-to" video on this).

Basically, you start by placing the center point of the garter at the outside of your leg. Then you cris-cross the garter around the inside of the leg, bringing the two ends back around to the outside. Then you tie them snug in a simple overhand knot. The final step is to then flip the ends of the knot up and under the garter, which will serve to hold the knot firmly in place. Then you fold down your hose and you are good to go!