If you are amumu you have to drive into fight by Q and then R.
To be more usefull and be more feeded u have to make lots of ganks and of course farm.

First what u gonna do is reb buff, after that golems or raptors and then u do what u haven't done before. When u are on bule jungle u doing wolves, blue guff, gromp, crab.

Pro's

• If u have some ap item u can one shot adc or someone like that
• huge engage in fight

Cons:

• easy to take lots of dmg from range champions
• early game: amumu easy to be killed 1v1 on jungle

Very easy, electrocute if u wanna be big ap bomb :)

Passive - Amumu's basic attacks Curse enemies for 3 seconds, causing them to take 10% pre-mitigation magic bonus damage as true damage from any magic damage dealt to them.

Q - Launches a bandage in a direction. If it hits an enemy unit, Amumu pulls himself to them, dealing 80/130/180/230/280 (+70% bonus Ability Power)magic damage and stunning for 1 second.
Cooldown: 10/9.5/9/8.5/8
Cost: 50/55/60/65/70 mana
Range: 1100


W - Amumu cries, refreshing Curses on nearby enemies and dealing magic damage equal to 10/15/20/25/30 plus 1/1.5/2/2.5/3% (+1% bonus Ability Power) of their maximum health each second.
Cooldown: 1
Cost: 8 mana
Range: 300


E - Passive: Amumu takes 2/4/6/8/10 (+3% bonus armor) (+3% bonus magic resistance) reduced damage from physical attacks.

Active: Amumu tantrums, dealing 75/100/125/150/175 (+50% bonus Ability Power) magic damage to surrounding units.

Basic attacks that hit Amumu reduce the cooldown of Tantrum by 0.5 seconds.
Cooldown: 10/9/8/7/6
Cost: 35 mana
Range: 350


R - Amumu entangles nearby enemy units, dealing 150/250/350 (+80% bonus Ability Power) magic damage and applying Curse. Entangled enemies are stunned for 2 seconds.
Cooldown: 150/125/100
Cost: 100/150/200 mana
Range: 550