After defeating Ultra Necrozma atop Megalo Tower and have returned the light to The Alola Region, the Ultra Recon Squad will allow you to use their Legendary Pokemon to continue to travel through Ultra Space. As you travel through Ultra Space, you will encounter and enter what are known as Ultra Wormholes. Ultra Wormholes come in different colors, each leading to a different area of Ultra Space. As you head further into Ultra Space, Ultra Wormholes will also behind to have rings appear around them. The more rings an Ultra Wormhole has will cause you to travel further in light years, increasing your chances of finding Shiny Pokemon, Legendary Pokemon, and Ultra Beasts.
The Controls while traveling in Ultra Space are simple, relying solely on the motion and tilt of your 3DS; however, you can change this to the Circle Pad by visiting the GameFreak Building in Heahea City. In order to gain speed and travel further while in Ultra Space, you will need to travel through orange orbs. Should you hit an electric orb with the Legendary Pokemon, you will slow down and risk being sucked in by an Ultra Wormhole. Blue, Red, Green and Yellow Wormholes will all lead to different locations in Ultra Space Wilds, all of which can possibly hold Legendary Pokemon. White Wormholes, however, will always lead to a place where an Ultra Beast resides.