You have to buy two light sabers and get two of the flat end caps. These need to be connected back to back by screw or epoxy resin or both. You then can attach a light saber hilt to both sides.
In Disneyland, you can create your own lightsaber at Star Trader in Tomorrowland (next to Space Mountain)
how to use twin lightsaber to become a double bladed lightsaber
Darth Maul used a red double-bladed lightsaber. Sith Lord Darth Traya used a green double-bladed lightsaber.
You get it when you talk to bao-dur when you have all the lightsaber parts you can choose 1 hand or double bladed
Darth Maul and Asajj Ventress
It would make more sense if her lightsaber was purple. It is the girlyest color of known lightsabers. No offense Samuel L. Jackson. Though it is possible that Disney will give her a pink one in the new movie current and/or flashbacks.
To my knowledge there is no style that allows you to change lightsaber styles. The only thing customizable are costumes, lightsaber crystals, and force upgrades.
darth maul by a stab of his double ended lightsaber in his chest
to get a dual lightsaber/ double lightsaber on star wars you need to be a sith inquisitor or jedi consular and get one of these advanced classes Sith inquisitor= Sith assassin Jedi consular= Jedi shadow
you can buy a lightsaber replica at master replicas
lightsaber
The list of the what-if Star Wars Force FX Lightsabers (with removable blades) are: Kanan Jarrus Force FX Lightsaber (Star Wars Rebels) Ezra Bridger Force FX Lightsaber Blaster (Star Wars Rebels) Grand Inquisitor Force FX Double-Bladed Spinning Lightsaber (Star Wars Rebels) Fifth Brother Force FX Double-Bladed Spinning Lightsaber (Star Wars Rebels) Seventh Sister Force FX Double-Bladed Spinning Lightsaber (Star Wars Rebels) Eighth Brother Force FX Double-Bladed Spinning Lightsaber (Star Wars Rebels) Savage Opress Force FX Lightsaber (Star Wars: The Clone Wars) Ahsoka Tano Force FX Lightsaber (Star Wars: The Clone Wars) Ahsoka Tano Force FX Dual Lightsabers (Star Wars Rebels) Qu Rahn Force FX Lightsaber (Dark Forces II: Jedi Knight) Yun Force FX Lightsaber (Dark Forces II: Jedi Knight) Gorc Force FX Lightclub (Dark Forces II: Jedi Knight) (downsized version) Pic Force FX Lightsaber (Dark Forces II: Jedi Knight) Maw Force FX Lightsaber (Dark Forces II: Jedi Knight) Sariss Force FX Lightsaber (Dark Forces II: Jedi Knight) Boc Aseca Force FX Dual Lightsabers (Dark Forces II: Jedi Knight) Jerec Force FX Lightsaber (Dark Forces II: Jedi Knight) Kyle Katarn Force FX Lightsaber (Jedi Knight II: Jedi Outcast) Desann Force FX Lightsaber (Jedi Knight II: Jedi Outcast) Tera Sinube Force FX Lightsaber/Cane (Star Wars: The Clone Wars) Ki-Adi-Mundi Force FX Lightsaber (Star Wars: Prelude to Rebellion) (colors: purple and blue) Adi Gallia Force FX Lightsaber (Star Wars: Episode I: Jedi Power Battles) (colors: red, green, and blue) Plo Koon Force FX Lightsaber (Star Wars: The Clone Wars) (colors: yellow, blue, and green) Saesee Tiin Force FX Lightsaber (Star Wars Episode III: Revenge of the Sith) (colors: purple, blue, and green) Even Piell Force FX Lightsaber (Star Wars: Emissaries to Malastare) (colors: red and green) Coleman Trebor Force FX Lightsaber (Star Wars Episode II: Attack of the Clones) Yaddle Force FX Lightsaber (Star Wars: Emissaries to Malastare) Oppo Rancisis Force FX Lightsaber (Star Wars: Republic) Yarael Poof Force FX Lightsaber (Star Wars: Zam Wesell) (colors: yellow and blue) Jacen Solo Force FX Lightsaber (Young Jedi Knights) Jaina Solo Force FX Lightsaber (Young Jedi Knights) Anakin Solo Force FX Lightsaber (The New Jedi Order) Exar Kun Force FX Lightsaber (Tales of the Jedi) Mara Jade Force FX Lightsaber (Mara Jade: By the Emperor's Hand) Corran Horn Force FX Lightsaber (I, Jedi) Lumiya Force FX Lightwhip (Marvel Star Wars) Darth Plagueis Force FX Lightsaber (Darth Plagueis) Darth Malgus Force FX Lightsaber (Star Wars: The Old Republic) Darth Bane Force FX Lightsaber (Star Wars: Jedi vs. Sith) etc.