This is my first guide so it isnt fullfilled yet, and btw my english isnt perfect either. But i bet u manage to understand whats written.

In the skill sequence I have recommended to max E as fast as possible, and dont Q, its because your Q isnt supposed to do damage unless you have been farming with it. Remember for each time u kills an enemy with Q, your damage on your Q will increase with 3+ damage, and it stack the more you kills an enemy with Q. So in late game your goal is to have at least 150+ damage so u does quite much damage with Q ability.

I recommend that you as nasus go solo top so u can free fam ur Q as fast as possible. Remember to only last hit minions to secure their gold. And i prefer that u play def no matter how bad the enemy is in the start.

Nasus is a great jungler with the right runes and items. But i prefer to go lane so you can use Q to farm whenever you want, and dont need to wait till its cooldown is over.

If the ap carry is fed, i prefer that u go mercury treads instead of ninja tabi, and if you dont need guardian angle, go a phantom dancer instead.