How to get faster at 100m and 200m sprints?

i went to a school event and i won both my 100m and 200m sprint by quite a bit, and im going to start training for the next year school event which ive been told i can take on to be one of the fastest in norfolk/suffolk, how can i train up to get my sprints faster? and what are the recomended running trainers? thanks! <3