The Championships UI is an awful experience. The notebook is a cool idea, but I found it very frustrating.
In Championships You Can't
- Edit your car
- Redo a race once it's been complete (Without resetting progress)
- Understand what's going on

A "Championship" in this game is using a preset car, with the co-pilot of that region. You'll do a series of races in each class (CL, RS, XR) and you get a podium based on the average of that set from the class. I believe you get the rewards just for completing the race, regardless of podium finish. Getting first just nets you more money.

I would recommend, before jumping into a championship doing quickplay or free roam. Pick the car that looks the coolest, and just try to get a couple runs under your belt. Then once you find a car you kinda like, take note of the manufacturer, and then go do a championship for that cars manufacturer.

In Rally you have a co-pilot sitting next to the driver. The co-pilot studies a topographical map of the area, and then typically do a "slow-run" while taking pace notes. During the actual race, they will read off their pace notes about upcoming turns. In real life pilot and co-pilot will come up with their own little system, but typically it's broken down the same. In this game it is slightly simplified numbering turns 1 - 3, square, and hairpin.

Hairpin
A hairpin (left or right) is a turn that is sharper than 90 degrees. On most maps in this game, it's usually just slightly sharper than a square turn, I haven't seen all that many switch-backs that require the driver to do a full 180.

For these turns, let off the gas a bit early and then brake into it tapping your handbrake at the last second to spin around, you wanna get right on the gas asap to start regaining speed.

Square
Square turns are 90 degrees. Sometimes you can get cheeky and cut the corner on them a little bit depending on how close the tires are stacked up on it, but overall I treat them almost the same as a hairpin except with less braking.

ONE
The sharpest turn that's over 90 degrees. These typically require letting off the gas and (or) braking, however depending on the track it is possible to angle yourself into it without even letting off the gas.

TWO
A medium grade turn, sometimes you can get away with just letting off the gas a bit, or tapping the e-brake if you want to try and drift it. Mostly depends on the car + speed

THREE
A slight curve. I usually don't even let off the gas for these unless I made a mistake and am trying to regain control.

There is no exact formula, especially in this game. Also be wary because your co-pilot sucks, I've had them call out a Square Right but I'm already ran through the tire wall. The co-pilot can be slightly improved by changing a setting.

Go to Options>Gameplay> Scroll down to "Co-Driver" and change it to Standard.

GOTTA GO FAST
It's kinda the whole point of the game right? Get to the finish line faster than everyone else.
If you're coming from other rally games you might be a bit frustrated and notice...
Traction is mostly boiled down to If you're on the road/path you just got faster, and if you deviate from the path you go slower. You want to try and stay on the center of the path as much as possible when going in a straight line. I don't know EXACTLY how it works, but I have noticed if at least 2 of your tires on the track, you will still be considered full traction. There are exceptions of course, cutting corners when you can will definitely save you some time in a low momentum area.
TLDR:

• Try to keep at least two tires on the course for full traction.
  
• Keep an eye out for ways you can cut corners.
  
• Keeping momentum is sometimes better than doing cool drifts.

Unfortunately there's not a ton of settings to play around with here, but there are a few that can make a world of difference. Most are subjective and may require tweaking around with depending on what controls you're using, but here is my recommendation for a good baseline.

Controller
Options>Gameplay

Sensitivity: 0.80
Deadzone: 0.09
Gamepad Steering Type: Linear
Co-Driver: Standard

Everything else I've got default. For the Gamepad Steering Type, the soft ramp or smooth ramp might be more comfortable for most players, but in the long run Linear is going to give you more consistent control. Linear essentially makes it a 1 to 1 for the input, instead of ramping it up with a curve. It's like mouse smoothing but for controllers.

I tried to keep the guide mostly short and sweet, but if I missed anything important, or if there's any info someone wants to know, give me a heads up and I may add it in.

I'm not a professional racer by any means, you most likely have not seen me on the leader-boards because I'm usually somewhere between 3rd and 5th and nobody checks there, but I do believe these tips will hopefully help someone.