"There are a lot of points that are very crucial and then a lot of it comes down to feeling - feeling the car with your backside. That is the main role of the driver - feeling the car underneath you. To make that car work as quick as possible from all those cues you get and sensations from your body - that takes years of experience. That is what I have been working towards all my life.
"All those little movements and feelings and sounds and then using those to put the right foot down or give it the jandal as Scott [McLaughlin] said."
A 13th placing on debut exceeded the expectations of many and he was widely praised for how he performed on such short notice.
At 27, Hartley felt he was in a better space to cope with the task but it certainly didn't mean things were easy.
"It is the fastest car on the planet," he said. "It was one of my biggest challenges to date - hopping into that car with the whole motorsport world watching.
"Tyre management, energy management, what it meant physically, racing in the slipstream of the other cars on the first lap - there were so many elements I needed to learn for myself and without finishing that race, I wouldn't have had the experience.
"The team didn't set me too many targets, to be honest, and they didn't put pressure on me."
Hartley admitted he has hardly had a chance to reflect on how big an accomplishment the past fortnight has been and what a watershed moment in his career it is.
"In two or three months, I will be able to look back and go, wow - Le Mans 24 Hour, Formula 1 debut in one year. That is something I won't ever forget - by far the biggest year in my career. At the moment, I am trying not to put too much thought into it and focus on the job at hand. The last few years have been in some ways preparing me for a moment like this."