Early Game

Jungle

Farm camps starting at red buff. Try to coordinate with midlaner @ 3:00 for river buff camps. You want to focus on getting gold as soon as possible for Barbaric cleaver. After that your farming will be much easier/faster so you can look for more ganks. Before ult, you have great diving potential, look for low health enemies that you can kill with a RMB and a Q then use the E + 4 for an escape. The early game ends once you have ult and Bonesaw. From that point on you will be able to go on a killing spree.

Mid or Offlane

Similar idea to jungle, focus on farm to get barbaric cleaver. Also potentially grab E second instead of Q for escape. You do not want to fight your laner at all until you have ult and bonesaw, so stay patient and play extremely safe, your time will come.

Mid Game

Jungle

With Bonesaw and ult you should be ganking whenever ult is off cooldown. Its best to look for lanes that are pushed up to your towers since you have a ton of movement and slows now. Particularly, look towards the duo lane and try to get kills that lead into securing fangtooth as well. When your ult is on cooldown clear camps, but also look to invade the enemy jungle. Unless they send a lot of people, you should be able to get away with it. After Mutilator, there really is not many people on the map that can stop you.

Offlane

Same as jungle except you should just begin to fight the enemy laner whenever possible. Your trades at this point should be easy, and you can escape with E if you go too deep. At this point you are also an extremely strong split pusher, so do not be scared to push under the enemy tower and try to take it. You will own that lane and try to stay in it to apply pressure to the enemy team. With Mutilator don;t be scared to try 2v1ing if the jungle arrives.

Mid

Everything is the same as offlane except, instead of pushing far up the lane, clear the waves fast and make sure to be at every jungle fight. Coordinate with your jungle to make plays around the map.

Optional Items

For optional items augmentation and citadel work almost every single game in whatever order you want to buy them in. The other items are very useful if the other team has certain strengths you need to deal with. Sky-Splitter should be built into high health/tank teams. Tainted rounds should be built against teams with high amounts of healing. Draconium is very strong into teams with low burst/extended teamfights. Salvation is a good option if the opponents are one-shotting you. Absolution is useful against teams with high amounts of immobilization and/or magical power. Dread is a last resort option if the enemy team has too much magical damage.

Late Game

No matter what build/role you play in the end game fights will go the same, make sure to have your ult active and dive the carry.