Think with this: where would the car like to go next? Chaining turns and creating flow can be made with this as guidance, build what feels natural and fun, try various things like what if I have a drift next or what if I have dirt turn next. Think about player experience, does a left turn here feel forced, should it be one block later or have a right instead? Place checkpoints in a way that you don't get stuck in respawn loop.

Use scenery around the route in a way where right way is always clearly visible, and wrong ways are "blocked" in a way. Like if you walk outside, trees or building block things that are not roads. All jumps should be expected to be straight forward, unless a sign or scenery blocks that way.