Infinite Items
Get a pokemon that can fly and one that can surf. Put the item you want in the 6 spot on your items list. Go to the Old Guy who shows you how to catch the weedle. Let him show you. After this fly to Cinnebar Island. Surf along the right side of the Island. You should fight a Missingno or a pokemon over L100. Knock it out. You should now have infinite of the item.

Safari Zone Trick
Get a pokemon that can surf. GO to the Safari Zone. Go to the area where the pokemon you want is. Waist all your time. It doesn't matter if you see that pokemon or not. Surf to Seafoam Island. You will find a small strip of land. Surf half on land and half in the water. You will fight Safari Zone pokemon.

Fight pokemon over level 100
Do the Missingno. cheat. Sometimes pokemon over level 100 appear. You can level them up to L.255 with rare candies, but then they go down to L.0. Although you shouldn't get into regular battles with them (they go down to L.100), you can battle a friend with them! There's more: you can even extend their HP bar. To do this, get them to L.255, then deposit them in a pokemon box, then take them out. Their HP will extend to the next line! Do this as many times as you want. I have seen they following pokemon over L.100: Bulbasaur, Charmeleon, Golbat, Muk, Magikarp, Electrode, Nidorina, Rapidash, Golduck, Starmie, Snorlax, Abra, Kadabra, Alakazam, Raticate, Electrode, and Mewtwo.

Master Ball Cheat
When you throw a greatball hold up and b it will act as a master ball.(hint: hold it right before it hits the pokemon) Or it might be down and b and you can also use down a A when the pokeball is just about to close

Easily Gain Level
To easily gain experience, simply switch the Pokémon you want to train with the top Pokémon on your list. When you go into battle the Pokémon will pop out. You can then switch to another Pokémon. Once you win the battle the beginning Pokémon and the fighting Pokémon will both gain experience points.

Celadon Slot Tip
All of the slot machines have different odds, which change every time. Play each machine 4 times, and if it hits 2 or more, then stick with that one, because it's probably hot. If the slow machine forces you really close to a 777 or Bar Bar Bar it will probably give you one or the other soon.

Free Coins At Game Corner
Walk around the game corner pressing "a" and you will find coins.

Phantom PC
Go to Celadon City and make your way to the motel. go to the far right wall and make ash look north and he be in the middle square. Press A and What's this? OHMYGOSH!!!! a Ghost computer!! Ok, so this isn't that big of a deal but it does works. Make sure you have your pokémon with CUT with you and go into the tall grass. Then use CUT. The grass will be gone and your injured pokémon won't have to fight.

Fish in a Gym
When you enter a gym go up to one of the statues and choose a rod to fish with. Usually you get good Pokemon.

Catch Ditto Easily
to catch a ditto easy put magikarp at the top of your list and let ditto transform into him and then switch pokemon you can also do this with a tentacool.