One of the most iconic portrayals of the fictional Jedi, is their weapon of choice, the lightsaber. A more elegant weapon for a more civilized time. Of course, such inventions are rooted in fiction, but even in this, there is a lesson to be learned by practicing practical swordplay.
I would not recommend trying to recreate the choreography seen in the Star Wars films. They are story telling inventions, and though impressive not everything is martially sound. In sparring, you will miss, you will get hit, and it will hurt. The idea in sparring is to do it realistically but to minimize injury. For this reason, I cannot recommend using so called “dueling sabers” no matter how much like the fictional lightsaber they appear, a light up blade designed to take the rigors of blade to blade contact will not feel nice against your body.
For sparring equipment, I would recommend either a padded weapon simulation, or the split bamboo sword used in Kendo called a shinai. Padded weapons can be made very inexpensively out of pvc pipe covered in foam and wrapped in tape. Its my experience that padded weapons tend to be a bit slower than a shinai and heavier. Though a hit from a shinai is not likely to seriously injure you will feel it and remember it. Because of the light weight of a shinai, I think the properties of the weapon is the best terrestrial simulation of a massless lightsaber blade.
Now as to the sparring style itself. I have trained in both Eastern and Western sword traditions and have developed a bit of an eclectic sword style. Nick Gillard, who developed the choreography used in the Star Wars prequels surmised that Jedi would use a fusion of all sword styles along with many other things such as tennis swings and tree chopping. Basically, any way to move a blade would be utilized by a Jedi. I think this idea has merit. While its important to first learn the fundamentals of a chosen sword style concentrating on proper position, distance, and strikes. Once you have a comfortable foundation, then you can learn to improvise outside of your style, but keep it martially sound. Another difference between free-sparring and choreography is that flashy moves are rarely effective. A good sword fighter will look good when they move not because of flash, but because of elegance.
Now a few words about sword fighting vs. fencing:
Fencing is a sport, it has rules and a sense of fair play. Depending on the style only certain kinds of touches or strikes will get you points, some parts of the body are out of bounds, there is a limited area in which you can move. And you never, ever touch your opponent's weapon. None of this applies to sword fighting. There are no rules in sword fighting, even in simulation the goal is to kill or disable your opponent before they do so to you. Though fencing is a fine beginning, it is my opinion that Jedi should not be fencers, we should be sword fighters.
Of course being armed with a sword in the 21st century is impractical, but the practice of sword fighting teaches things that would come into play in unarmed combat such as position, distance, and timing. One of the eastern sword traditions I practice, aiki-ken, informs the empty handed forms of aikido, which is derived from ju-jitsu which in turn were the empty handed techniques of the samurai and were based on sword mechanics. Then there are the benefits that come from discipline, hard work and training one will need to do to become proficient at sword fighting. Lastly, its fun!
Now using a shinai or a padded weapon to simulate lightsaber combat, injury and death will likewise be simulated (hopefully!). I suggest starting out slowly and building up your speed over time. Any contact to the body and the spar is over. In training it is to the first touch. Glancing or light blows can be ignored. But to be sportsman like a good rule of thumb would be to “hit hard and take light”.