** Gadgets: Unless you are a good runner you will not know the exact speed at which you are running. A GPS gadget will give you feedback on your race pace and let you know whether or not to speed up or conserve energy. I use one. A tactic is to set it to beep at you when you are going at a pace that is, say, 4 seconds per Km faster than your target pace. When it bleeps slow down BUT otherwise run as hard as you can.
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.