When you get to the town with the first gym, don't head to the gym straight away. Go to the top right exit of town and to the dream yard. There talk to a lady who will give you an elemental monkey, Pansage, Pansear, or Panpour. The one that you get depends on your starter Pokemon. You pick Oshawott you get the fire monkey Pansear, Snivy you get the water monkey Panpour, and if you get Tepig you'll be given the grass monkey Pansage. Now that you have your monkey go ahead to the first gym, your monkey will have a type advantage over which gym leader you battle.
Added by: Ninetailed Fox Feb 28th 2011, ID#15317