This shyvana build is the one I use when I solo top with her. I tried almost every item composition with her and this one is the one that proved to be the most effective one.

My guide is far from being complete so comment me what you would like me to add up or change I could make in it.

I use offensive masteries because my main objective is to do alot of damage in team fights and be able to substain damage with life steal and couple of defensive items.

Is you prefer going defensive masteries it might work as well, but your damage output will be slightly reduced but you will be able tank even more damage.

Since Shyvana deals both magic and physical damage. Havoc and Archaic knowledge are very good on her since they boost the magic damage output that she isnt spec in it with the item build . Havoc is also working on the physical damage aspect of the game.

I saw the runes that were used in the champion spotlight and i was like T_________T. Siriously? Why would you need health regen. if you didnt noticed, FoN, Warmogs and stark fervor get you a large amount of health regen without even counting the FoN passive effect. Life steal is also another healing factor. In that case i use armor and magic resist lvl 18 because i want to be even more tanky and since i know that attack speed is really good on shyvana I use attack speed runes as my main runes on this build.

The alternate runes i would suggest would be flat armor seal, flat magic resist glyph, dodge seal (if your going defensive masteries with ninja tabi THIS would give you about 21% dodge witch could be very good and 25% with some quintessences It would give you a great advantage against any ad champion)