Instructions
Turn the Nintendo DS system on and press "Start" at the title screen. Select "Continue" and press "A" to continue your adventure.
Travel to Pallet Town and enter the house on the right side of town. This is Blue's house. Make sure you have a Pokémon at maximum happiness.
Talk to the girl in the living room at anytime between 3:00 pm and 4:00 pm. This is Blue's sister. She will massage your Pokémon. After five massages, she will give you Blue's phone number.
Press "Start" and select the "Items" menu. Select "Pokégear" and call Blue. A rematch will be scheduled for Sunday night.
Travel to Viridian City and enter the gym. Blue will be at the end of the gym.