How do i beat the elite four in Pokemon diamond?

I have a level 74 Dialga(Cut, Fire Blast, Roar of Time and Earth Power)___. 70 Infernape (Fire Blast, Hyper Beam Rock Climb and Strength).___50 Azelf( Confusion, Uproar, Future Sight and Nasty Plot).___42 Roselia ( Stun Spore, Petal Dance, Taoxic and Gr Whistle).___42 Bronzong ( Iron Defence, Safe Gaurd, Gyro Ball and Block).___ 34 Snowver ( Swagger, Mist, Ice Shard and InGrain). Please Reply ASAP!