best way to max at NMZ

It really depends on how AFKable method you are looking for.

Guthan is most afk without need to click on Absorption Potions, but the XP rates are so terrible I wouldn't recommend it.

Obsidian armour + sword + berserker necklace is the fastest and very afkable method till about 95-99 Strength
Definitely don't use SS, if you can afford obby set.

Dharoking with rock cake on a Hard Mode is starting to be a better XP/h on 95-99 Strength
and if you start dharoking I would recommened getting your attack level to 90, before finishing 99 strength.
This method is however not very afkable with the need of clicking on rock cake/pray flicking rapid heal.
XP/h is better only by 15-20% from the maxed strength training, so if you want to AFK a little more, you might prefer staying with obby.

PS: Community General is a wrong section.