Shyvana is a strong melee fighter who has natural resistance to damage built in, and in my opinion does not need much survivability to compete with other common bruiser type characters. This build is my recommended item set but obviously you should always build situationally and react to the enemy team. IF you find yourself commonly being focused down I would recommend building a Warmogs Armor over turning Phage into Frozen Mallet because it is much more cost effective.

Standard ArPren rune set with some defense built in for the early game. After level 6 the passive on her ultimate really helps your survivability and in Dragon Form you become and unkillable beast.

I would consider Wriggles Lantern, Wit's End, and Trinity Force to be core on Shyvana. Boots really comes down to your boots of choice, I personally like the extra attack speed. Past that I find that a phantom dancer gives you a ton of extra damage output while helping to chase people down, which is critical because this champion has no hard CC. You could also introduce a Black Cleaver instead of a Phantom Dancer. Last slot can be a health item, as stated before I would recommend Warmogs.

I take flash and ignite, though ghost might be a decent choice if you don't like flash. Ignite really helps with early kill securing, though could be swapped with exhaust as it helps you to stick on champions much easier.