*** Run in straight lines. ie run 5k not 5050m from wandering all over the place. That extra 50m will take you probably at least 10 seconds to run, which is a LOT. Running ‘straight’ requires great focus throughout the race and involves NOT following the person in front of you (usually)!! Think about it if you don’t at first get what I am saying. Also if you are using GPS pacing remember you run further and so need to pace slightly yourself slightly quicker than what the GPS/HRM says to take that into account. ie Your GPS probably show you have done 1km before the 1km point of the course.
All the suggestions are starred:
*** 3 stars. IMHO it will work
** 2 stars. It might work
* 1 star. Can’t hurt
X 1 cross. It CAN hurt if done wrong.
All 50 tips are shown here as a series of posts : https://the5krunner.com/tag/how-to-get-a-5k-pb/ or on twitter using #howtogeta5kpb. They are all SHORT-TERM tips that will work in the next week or so with varying degrees of success.