Counter jungling is fun and rewarding, but sometimes it is necessary to counter jungle your own jungler. It is frustrating in solo queue when your teammates are just complete ****, so it is time to take things into your own hands. The buffs may be more important on you.

I use mana regen runes all the way, because nunu is mana hungry. The gold per 10 helps him scale better lategame, when nunu is just a monster. For masteries i put all into utility for obvious reasons. Start out with as many health pots as you can afford, and as soon as you take damage pop all of the pots. Just keep clicking on the hotkey until all pots are popped at once. This gives you constant health regen and is better than any other health regen item. I get wards to ward my own jungle so my jungler will not steal them. The quicksilver sash is the cleanse blue or red buff because they weigh you down and you move slower.

Make sure you pick some other summoner, than switch to smite at the last second. This is so your jungler does not suspect. The promote is used to promote blue buff, to make killing it harder for your jungler.

Tell your jungle you are leashing for him. When the buff is at around 1000 health, quickly q and smite it. Follow jungler and repeat. Your team will thank you, beleive me.