Go to route 29 in the Grassy feilds to the right of Cherrybloom town or whatever it's called.
Talk to your Pokemon a lot or just walk around. You will eventually get to battle. I find battling the easiest way to level up. In the grass feilds, the most common Pokemon are Pidgys and Sentrets. They are weak, so you should find it easy to beat them.
Chat with our AI personalities
-rare candy(although people say that its not good, but it can bring your poekmon to a higher level, making EV training more effective)
-lucky egg (wild chancey hold... 5%)
-trade (150% increase)
Easy. Give him or her an Experience Share, then battle a high level pokemon.
the easiest way to level up your Pokemon to put it in daycare Pokemon will level up soon.Trade the Pokemon to friend and have it hold a lucky egg it will level up quickly.
The easiest way to level up is to feed Pokemon Rare candies.
a easier way of leveling up is below! Pokemon level 1-30 find a level 50 Pokemon Pokemon level 31-100 find a level 100 Pokemon Pokemon level 101-200 fight a level 200 Pokemon Pokemon level 201-300 fight a level 300 Pokemon and so on... WARNING YOU MUST DO THIS ON VERY EASY!!
fight the elite four