This comic will focus on reference points, vectors, and velocity.
GPS Coordinate Plane
This is ROVER 2, the vehicle that transported Mark to his rocketship. It is realistically about the size of a military tank but it was retrofitted with oxygen tanks and H2O conversion tanks which is beyond science capabilities as of now.
The Sandstorm
Mark's issue when traveling across the face of Mars was that he had no way of calculating how far he traveled through technology. His first way was to use GPS and send signals up to the spaceship/satellites in orbit around Mars.
Backup Plan
The concept of GPS is based on a coordinate plane. NASA already had satellites orbiting Mars, so when Mark arrived, he had his location pinpointed at all times.
Mark began on his journey but almost immediately his GPS and communications broke in a sand storm that thrashed his ROVER, which he had to make repairs on.
It is really hard to travel during the day because it gets very hot. At night it also gets very cold, but I have developed a way to produce heat.
Back at his base before leaving he had created two more methods of travel if his GPS had failed. One of them used the circumference of the wheels and the RPMs at which the wheels turned at. This was a very risky maneuver but it was one that he had to take.