Jean-Philippe Mateta put Palace ahead before Danny Welbeck found an equaliser. But Daniel Munoz struck in the second-half for Palace as they eventually won 2-1. Palace also had Eddie Nketiah and captain Marc Guehi sent off, with Brighton defender Jan-Paul van Hecke also seeing red.
"We just showed them which system they need to play," Glasner told PalaceTV. "And they knew what to do. One or two situations changed, with Daichi (Kamada) as like a left wing-back.
"It was not so difficult because we often train nine vs ten, sometimes eight against ten - but not so often!
"But the players know what they have to do. What I really loved today is that they didn't just defend and wait for the referee to end the game.
"We were waiting for the right moment to go forward, with Daichi forcing the red card, otherwise he would have been one-on-one with the goalkeeper. This mindset I really loved today."
Glasner admitted he was proud of Palace's performance and also being part of the spectacle on the day.
"At the moment I'm exhausted," he said. "Because this game had everything, it's why we love football.
"The atmosphere today at Selhurst was really amazing and everyone goes home happy.
"This group of players... it's a massive achievement, 92 years (since) for us to win both games against Brighton. It's a massive win and we're pretty happy.
"We had to defend all their crosses, they had one free header where we were lucky, but everything else we defended really well. We stayed calm and were fighting for every single ball.
"It was a great experience for them and gives us so many emotions, it was fantastic."