This is a guide for people who want a bit more stab with nautilus but retaining his tanky ability.

You'll want some attack with your masteries however since you arent going to be as tanky you might go 0 21 9 as well.

Always start with boots 3 because nautilus is fairly slow and with boots 3 you can take some harass. With the pots though try takin dredge first so you can harass early as well.Start with a rod of ages a common ap tank item. Then go for frozen heart to get early tank. A tip is to farm heavy and get an early kill. Then you will build abyssal scepter and sun fire cape as they give you some ap and tank plus they work hand in hand. For boots you could go with merc treads but also try boots of mobility, ionians and ninja tabis really depnds on the situation. To top it off you can get a frozen mallet to get some stab on your basic attacks. You could sub it off for a guardians. I found these items particularly easy for kills and early dominance, however with an ap build just be aware you arent as tanky as you were with a standar tanky build.

Ignite and flash are good. Gets the kills and gives you an escape but really ingite and ghost work better . You could also use exhaust and flash but you have enough cc for exhaust.

Tanky but able to pick up kills. Peeks or shows early game lane dominance, interesting and fun build

Cons
If you are used to a tanky build be careful because you arent pure tank anymore

Pick up blue whenever you can. Because you will be going for kills and with blue you will be able to spam abilities.

Initate with a basic attack if possible , however try isolating targets as this will let you escape being targeted.