How do you beat your rival?

Answer 1

to beat your rival find the weakneeses of your rivals Pokemon like if you chose a grass type and your rival has a fire capture a water type or tran real hard teal your at a higher level than your rival

Answer 2

That would depend on who your Rival is but if you're playing FireRed or LeafGreen then your Rival is Blue and the Pokemon he uses throughout the game would include Pidgeot, Alakazam, Rhydon, Exeggutor, Gyarados, 1 of the Starters and when is the Champion he also adds Arcanine to his party. Pidgeot can be beaten by Electric and Rock-types, Alakazam can be beaten by Ghost, Bug and Dark-types, Rhydon can be beaten by Water and Grass types, Exeggutor can be beaten by Fire types, Gyarados can be beaten by Electric-types and Arcanine can be beaten by Water-types