Firstly, I'd recommend playing ranked games as the players you face will quickly get you up to speed just by racing against them, no pun intended. You can really learn a lot from better players which will benefit you greatly when dealing with the unfair bots, which will seem like a breeze in comparison.
Secondly, I've included videos of my completion of the four chapters on unfair difficulty, which will hopefully give some insight into paths, item use, and spots where the bots seem to mess up a lot
Good luck!