The first link here is very informative on how to apply kicks to a street scenario. People know that kicks are very powerful, but the reason that most don’t use them, is due to the speed it takes to set it up and because of opening their defense. This video shows how to defend yourself from straight right punches and also get the kick off onto their lead leg.
This next video explains why you should NEVER kick above the waist. A kick straight to the shin or to the knee cap is WAY more effective than trying to kick them in the ribs or the head. The possibility of getting your foot caught is higher the higher you kick!
I hope that these videos help you out with your kicks in a real fight! Just remember to make your kicks fast!!! It may feel as if you have no power, but trust me, you are kicking harder than you realize.