After the events at Spear Pillar, head east from Mount Coronet (the route leading to the Spear Pillar) to reach Route 222. This is a coastal route with several trainers. Continue east, and you'll reach Sunyshore City. In Sunyshore City, you'll find the Sunyshore Market, where you can buy various seals for your Poké Balls. You'll also find the Lighthouse, where you can speak to Flint of the Elite Four. Your rival, Barry, will challenge you to a battle near the Gym. After defeating him, you can challenge the Gym.
