Depending on the terrain, weather, wind, speed you actually drive, and your mental comfort factor (familiarity with range anxiety), you will probably use this as a learning curve course.
The range of your car is based on testing, close to 65 mph. Faster the driving speed, greater the wind resistance = greater use of charge in battery.
Due to current number of locations of Superchargers, and your anticipated number of scheduled stops, what might be a 14 hour drive in an ICE could easily become 16 or 17 hours in an EV. Any EV.
Because it is a Model S, it will not charge as quickly as a Model 3.
Before you leave, Plot out your anticipated route. Your car can do this for you, just type in end destination point, and the car will guide you.
It will identify all the Superchargers on your route. You should learn to ZOOM in for Supercharger locations, because many times, they are located to an out-of-the-way location on a site.
You should plan to have enough energy for each destination, plus an adequate amount of buffer charge, say maybe 50 to 70 miles extra. This can possibly be reduced as you learn more about your car, and your driving style/speed.
It takes a really long time to fully charge a Model S (anything above 80%), so more stops allows for quicker charging times. You should never need to charge to 100%, unless you are really stretching distances between Superchargers. Maybe next trip, after you have driving experience with your car.
Know your terrain for each leg of your trip.
Mountains will kill anticipated range going up, and give you unbelievable long range going down (thanks to regen).
First couple of legs, get familiar with your car and your driving abilities. If you get tired, maybe switch drivers or maybe check into a hotel.
It can be a lot of fun to learn new stuff (and some you can only learn by the experience of doing), just be adaptable to existing and projected range for each leg of your trip. If your speed can safely be reduced so that you make it to next charging point, you might need to drive a bit slower.