which key stones should i be using on top lane nautilus?

Aftershock is better later on in teamfights, Grasp is better early on when trading in lane.

It depends if you plan on battling a lot in lane or if you expect to just stay passive and survive while soaking xp.

Aftershock vs ranged champs and bullies you cant trade with. I've always been using aftershock but maybe grasp is good in other cases, I will have to try it.

Outside of the standard stuff already suggested you could try out Unsealed Spellbook. If you really like fighting and trading and are confident in your ability to survive jungle ganks take ignite for the extra kill potential, and if that doesn't work out switch to teleport.

After shock

You dont have the mana sustain nor the low cds for extended trades in the top lane. Get in, do your damage and back out again. Repeat when after shock is vaback up

Bring transcendence+ultimate hat because his cooldowns are overkill lol

top nautilus? normies or ranked cause if its ranked maybe don't go top anywayys i would bring some tank masteries (grasp maybe) because he is just so tanky later