From Bulbapedia, the community-driven Pokémon encyclopedia.
Turn the Game Boy on. After the intro, press A or Start on the title screen and you'll see the main menu.
You should be able to select from New Game and Option. (You may have Continue as a selection; this is if you have already started and saved a game on this cartridge.)
Moving the cursor to Option and pressing A will show three topics. You don't need to touch them, but it's a good idea to put the Text Speed to Fast. Go down to Cancel and press A, and you'll be back on the main menu. Select New Game and press A.
Professor Oak appears! He briefly introduces the world of Pokémon and the Pokémon themselves. Then he asks for your name.
|| Default Names
|| Red, Ash, John
|| Blue, Gary, Jack
If you don't want any of the preset names, go to New Name and press A. Here it's a simple case of moving around to the letter you want and pressing A to select it. To remove the last letter, press B. Once you're done entering your name, select End in the bottom right corner or press START. This stumped a lot of people when the game was first released.
Now you are introduced to your rival! Choose his name in the same way, and you'll be teleported off to your bedroom in Pallet Town!
The game begins in your bedroom, with you standing in front of your SNES. First of all, here's a recap of the controls:
| Moves the character; moves the cursor in a menu
| A Button
|| Talk to people, push buttons, examine things
| B Button
|| Cancels selection, exit a menu
|| Opens the menu
The PC in the corner is your item storage system. Your backpack can only hold 20 different items, while the PC can hold up to 50. Deposit Item and Withdraw Item are self-explanatory, and Toss Item lets you get rid of an item permanently. The PC already has a Potion, so select Withdraw Item and choose Potion ×1. Press the B Button to close the menus and return to your bedroom.
To save the game, press START. Select Save, and then Yes. When the menu disappears, your progress is saved. You could then turn off the Game Boy and start from this point at a later time.
To go downstairs, step on the stairs in the top-right corner of the room. Mom is sitting at the table, and tells you that Professor Oak has been looking for you. To leave the building, step on the mat along the south wall, and press down on the D-Pad. Welcome to Pallet Town!
Pallet Town is a rather boring, quaint town, with only three houses. The house to the west is yours, the one to the east is your rival's house, and the big building to the south is Professor Oak's Lab. You can walk all around town and talk to everyone, but Oak is nowhere to be found. Looks like there's nothing else to do but leave town, so walk into the tall grass north of the town...
From out of nowhere, Oak appears! He yells at you for trying to leave by yourself, without a Pokémon of your own for defense against the wild Pokémon roaming around. He drags you back to the lab, and lets you choose your very first Pokémon. Each one has its advantages and disadvantages, and some are more challenging to raise than the others.
- Bulbasaur is perfect for beginners. It can easily mop up Pokémon in the Pewter, Cerulean, and Viridian Gyms, and resists the Pokémon in the Vermilion and Celadon Gyms. It is also unaffected by the Poison status ailment. It may have trouble with the Saffron and Cinnabar Gyms, but at that point in the game you should have some great Pokémon to back it up.
- Charmander is the most difficult Pokémon for beginners to use, since it will be at a disadvantage in the first two Gyms, with its only advantage against the Celadon Gym. His final evolution, Charizard, is noted for being quite powerful, though it may not usually have a type advantage in battle.
- Squirtle is the second-easiest to train. It can defeat the Pewter, Cinnabar, and Viridian Gyms without much effort. However, its movepool is relatively limited, and it may have trouble against the other Water Pokémon in the Cerulean Gym.
Once you have chosen a Pokémon, it's your rival's turn; he will always choose the Pokémon with an advantage against yours. When you turn to leave, he will challenge you to your first battle!
When battling, you'll each send out your Pokémon; they are Level 5, which is shown by the :L5 aside each Pokémon. Under that is the health bar, showing each Pokémon's remaining HP. You win a battle when you take all of your opponents Pokémon down to 0 HP; you will lose the battle if all of your Pokémon reach 0 HP.
Choosing Fight will allow you to choose an attack to use against your opponent. Your Pokémon will have two attacks regardless of who you chose. The first will damage the opponent, and the other one will lower one of the opponent's stats. Keep using the attacking one, either Tackle or Scratch. If your Pokémon starts to lose a lot of HP, you could use that Potion we got out of the PC earlier; go to Item and it will bring up a list of the items you are holding. You only have a Potion, so select it and then select your Pokémon. This is the same way you use the Item menu outside of battle. Once you have defeated your rival, you will get 175, and he will leave. If you win the battle, your Pokémon will gain enough experience to grow to level 6.
Leave Oak's lab and head north to reach Route 1.