One point that is worth remembering is that you can make it a lot easier for someone to help you by always facing out of the parking spot whenever possible (backing into it or drive through). That way your battery is much closer to the car from which you are getting the jump.
Also, if you are making your own cables and all you have is smaller guage wire (say, ten guage), you can double up the wires and gain three guage sizes per doubling. Two #10 wires = a #7 and four #10 wires = a #4 guage equivalent.