In some cases I may swap the 3 quints for movespeed quints.

If enemy team has a lot of AD champs like tryn, jax, yi or things like that take exhaust over ignite.

21/9/0 masteries for damage but sometimes I'll grab 9/21/0 if I need the extra tankiness early game.

Early Game: 1-5
You aren't tanky yet, just try to farm and play safe. You can poke with your Q after you get blasting wand and farm with it. Just make sure to keep your mana. Focus on farm and zoning.

Mid Game: 6-11
Build stacks on your ult as fast as possible. Don't save it unless you are about to teamfight the enemy. Use it as soon as it comes off cooldown. You are getting tanky. Use that to your advantage. Stop poking with Q and start poking with W. Further execution explained in end game.

End Game:
You are a tank. Be protective of your stacks you need them but you are hard to kill. Really hard. Initiate fights by walking in to the enemy and attacking. Lead with W as you go in. They will either engage, or run.
- They engage: Use your Q under whoever they engage on. You will do a lot of damage and your team should focus that target. Fight is now 3v2 in your favor. Don't hesitate to use feast on this target.

- They run: You may be able to drop Q in front of one of them. Likely to hit the back one but may miss all 3. Regardless you have now separated their team. In order to dodge it the one n the back had to slow or move towers your team. Focus down this now alone target ASAP.

The trick to the Q is keeping it available more than using it. They will be more afraid to engage when you have it. It works best as a secondary engage ability and is as good as a sona ult if not better when used like this. It will single handidly make the other team unable to dive you. You can hold a tower 1v3.