Crappy 100m time! How can I improve it?

sort your reaction time out !, sort you stride length out, e.g short strides at the start as soon as you hit 40+ meters change to long strides. (short strides= acceleration)(long = top speed) also do some 60 meter sprints and then see your time since that's when every one seems to start struggling so if you have a time for 60 meters then you can work on the last 40 meters which is were you lose most the time.