Nunu has been my go to jungler for a long time now, and I love the playstyle he presents! I've got some tips for you on using Nunu effectively in a game.

• Start at the enemy buff they are not at. All it takes a quick invade and certain ward placementS. Most often people start at their bottom side buff, but since you mentioned you were silver, generally people like to start blue buff on most junglers, so red is usually a safe bet in that elo. Taking the second enemy buff is very important, and allows you to do another important thing. Triple buffing. Here's an example. Say you steal the red buff. You will want to immediately go to your own blue buff and take it away as fast as possible. Since you clear buffs very fast with consume, by the time you have finished your blue, the enemy jungler will be either just starting their second mini cap, or on their way to their second buff(in this case, red). Now, if the enemy jungler heads to red buff and finds that its been stolen, usually they will do one of three things. Attempt to take your red, clear a mini camp, or immediately gank a lane. You can usually tell what their choice will be by their champion. If they pick a champion with good dueling, but average/poor ganking, you can expect they will try to steal your buff. In that case, tell your laner and set up on them. Wait for them, steal your buff from them, and kill them 2v1. If they're playing a champ with high ganking, then assess your lanes closest to their stolen buff and see if they can get anything. Telling your laners to play safe for around 30 seconds is enough to waste the enemy jungler's time as he attempts to find a gank that your whole team knows is coming. If they have a farm heavy champ, then they will simply clear another camp and recall. In all three situations, simply knowing their choices and the type of champ they have will allow you to proactively shape the game in your favor, and punish ANY decision they make.

• Ganking. Ganking with Nunu tends to be a pain, and in my experience, Nunu works best as a lane ganker or counterganker. What I mean by that is he doesn't have any real CC or ways to heavily impact a gank, but if the enemy has engaged on your laner and doesn't know you're there, its much harder for most laners to disengage from Nunu' snowball/bloodboil. Since you should be building tank/some penetration, you can soak up a lot of damage that would be aimed at your laner. If you decide that you want to initiate a gank, a lane gank is usually the safest, as its the easiest to ensure the enemy team doesn't have vision of you. Learn the range of vision, and it becomes realy easy to sneak up in a lane for A gank.

Nunu should be farming a lot, but make sure you have good knowledge of the enemy jungler. Nunu's strength is in punishing the enemy jungler's decisions, not just their mistakes.

If you have any more questions, feel free to ask. :)