You begin the game in your room. Take this time to get used to the controls.
You hear a large boom and some sirens. Ness gets out of bed. From here, walk downstairs. This is where you get acquainted with moving and talking in EarthBound. Talk to your mom, who has also heard the noise. This conversation will let you know that you are to go check out the noise. Another humorous aspect of the game the reaction of Ness' parents to his desire to save the world. Mom and Dad will be nothing but supportive of Ness' wish to go fight evil, as long as you "at least change out of your jammies before you go."
You then start back in your room, fully dressed. Continue outside. Now just follow the path to the West around to the top of the hill, being sure to grab the bread roll from the present. Also, try to talk to everyone on your way to get the hang of interacting with NPCs and to get clues as to what your next steps will be. The text-heavy nature of EarthBound may seem slow at first for modern gamers, but the subtle humor of the game and the full effect of the railroad-style RPG is lost if you ignore the NPCs.
At the top, you can see the meteor glowing, but the police have set up a blockade so you can't get by. Pokey, your neighbor, is bothering all the cops. Talk to everybody and Pokey will tell you that he will give you more info on the meteorite tomorrow. The result is the same whether or not you say you are friends with Pokey. You must learn to take subtle clues like Pokey's in order to know that you have to go all the way back home and "wait for tomorrow." Your mom should be outside once you have spoken with Pokey, and she'll tell you to go back to bed. Say yes.
You'll wake up again. Go downstairs; there'll be someone knocking on the door. Pokey will tell you he lost Picky, his brother, and ask for your help. Then talk to your mom again, and she'll make you change into regular clothes. Stop in your sister's room for the Cracked Bat. This is your first weapon. Equip it. When you get downstairs, talk to your sister for a Cookie. Also, talk to your dog and Pokey to make them join your party and head outside. Before you can leave, the telephone will ring, and you will talk to your Dad. By calling him throughout the game, you may learn your bank account status (he will deposit money as you win battles) and can save your game. He will also be extremely supportive, almost living vicariously through your adventure.
This time, wild animals will attack you. Try not to face away from the enemy or it will get an extra attack. Make sure to fight and gain a level or two to get used to the battle system. If you need health, eat the Cookie, (you can gain more cookies by defeating Spiteful Crows), use Lifeup Alpha, or if you have no other option, return to your house to get a meal. Be careful, because the crows can also steal Cookies or other foods from you.
Keep going up the path and battling the animals. Once you get to the top of the hill, the blockade should be gone, as the police are dealing with the Sharks. Go up past the meteor. There, your dog runs away out of fright. Go and talk to Picky who is sleeping near the meteor. Welcome him to your party and start to leave. A cut scene with Buzz Buzz will be triggered which will reveal the main plot line.
For whatever reason, a bee from the future comes out of the meteor and explains the story. He says that in 10 years, Giygas will take over and you can only prevent it by acting now. He will then join your party. Again, head back down the mountain. When you get to the end of the path, a Starman Junior will appear for your first boss battle. Don't sweat it though because you can't lose!
Head on to Pokey's house and just walk in to watch a cutscene. Pokey and Picky will get in trouble and then their mother kills Buzz-Buzz. Talk to him, and he'll say some last words and give you the Sound Stone (or leave it in your sister's care if you managed to max out your inventory. This is an important item, but it activates automatically, so don't worry about it). When you go outside, the night will turn to day, and you are ready to begin your adventure!
If you go back to your house again, you can get a picture from the camera man and heal or save. Your mom will always Heal you if you talk to her by making you your favorite food. Now, you can go to the main part of town through the east path.