As you all know, I'm one of the more dominant players on the server. It's not easy getting to my level, but maybe someday if you perspire you can reach me and even surpass me (good luck tho). Not all hope is lost tho. As many others can attest to, I used to badly suck too. These are some tips that will help you improve your skill a little bit more, although do remember you aren't going to go from F-D tier to epic prorunner overnight. A lot of your more advanced playing skills you will have to learn yourself, and figure out what's best for your ping.
BASICS:
Speed is one of the most important thing when it comes to zs. While every player moves at the same rate with regular straight running, you can use WD/WA combination keys to diagonal run which is slightly faster. When diagonal running, you will have a blind spot on your other side, so choose to face the direction with the most oncoming zombies. Another big benefit with speed is to choose the most efficient shortest routes, and parkour smoothly while avoiding 1 block jumps that slow you down if possible. The biggest thing on getting around the map fast is not missing your jumps, so master those.
Depending on your ping, every player on your screen will be about 1-2 blocks ahead of what you see on screen. In some extreme cases with 80+ ping, reach distance could be 1.5 + blocks. You will need to be in front of a player at this distance to infect them, and ahead of them at this distance to avoid being infected.
Human are noted in Green, and zombies are noted in Red.
Honestly, I wouldn't recommend using a lot of these moves if you don't have to, but you will need to use jukes as you will find yourself in tight places. Remember to make your jukes tight and quick as gods like me will easily intercept them. Try limit yourself on back jukes as those are easier to intercept. The black arrows are the current movements of players, while the pink arrows are the possible jukes a human can take, and the dark blue arrows are the possible jukes a zombie can take to predict the human. The light blue arrows are a possible route a zombie might take.
If you think you're cute doing a bunch of jukes, then you're wrong. Jukes is not prorunning, and should be used only when necessary if you're aim is to survive. In actual prorunning, you should always be aware of where the crowd of zombies is at and what direction they are moving. You then need to plan ahead and look for open space. When looking for open space, try to take more unpredictable routes to keep the zombies on edge.
It's very hard to draw out playing zombie so I will write a brief description. Playing zombie is what makes you a man. Not to brag but I am the 3rd best zombie according to NB awards. If you can't kill others, you are not a prorunner and you are weak.
To infect a human, you need to do a "flank". A flank is going in a diagonal line to aim yourself about 1-2 blocks ahead of a human. Most decent players will notice this flank and will juke or change course before infection. That's when you pull out your predicting moves, although remember not to fall for every small juke as good players will implement micromovements.
Playing zombie is mostly about getting ahead of players or using the map surroundings to cut them off. Use all the human jukes that were listed earlier, and deconstruct those to be one step ahead of the human.
Here are some videos to show you prorunning at a simple level. At first you want to master the basics, then start playing riskier to break over that C - B tier gap to become one of the elite. In my videos, I use 130 fov and shadow circles. I recommend atleast 100 fov and shadow circles. Remember that zs is not looking at the ground.