How do you get sixth badge in Pokemon Red?

Answer 1

You have to get into Saffron City. To get in, you must pass the guards. To do this, you go to the Celadon City Department Store and go to the top floor, to the drink machine. Buy a Water and take it to the guard. She will ask for it, so give it to her and she will let you through to Saffron. Defeat Team Rocket in Saffron City (Silph Co) and also under the Rocket Game Corner. This is done by looking under the poster there. Now you can go into the Saffron Gym for the sixth badge. Defeat the gym on Cinnabar Island and the Viridian Gym and now you have all eight badges. (This is if only if you have defeted the other gyms, too)