Hello i love playing Nocturne and so i made a build of him that i think works best for me. it's a very simple build so it's a kind of a "newmans build" to nocturne.

The rune choise is super simple you can master these how ever you want to. Let's say you need to be more tanky for your team then switch some AS and AD runes to resistance runes.

Theese masteries works Very fine for my playstyle i take lifesteal becouse i steal jungle buffs from the enemy team. and the life and resistance becouse i like to be abit tanky so i dont get carried down in teamfights to easy.

Theese items is a great choice for nocturne you could replace the wriggle's to something else. But IMO i like having some lifesteal and mapcontroll in the lanes and i dont like losing health after iv'e taken jungle buffs, so i can directly rego to my lane and dominate instead of recalling.

The Q spell is a very important spell for nocturne, It gives him more attack damage and movement speed when you stand in it's liquid. For example you have just taken red buff and going back to the lane, just Q them and you will easly get in attack range in no time.

Mobile
Good ganker
easy to master
very good damage output

slips of a bit lategame
usually get targeted in teamfights

Jungling: you should make sure to keep there red and if possible blue down as much as you can. so every 5 min you should go and steal there buffs. Remember to always kill the dragon each time it spawns (6 minutes spwantime) It's a key to Victory!

Try to hit as many enemys you can with your Q and passive in teamfights and it's your choice if you want to use the ultimate before or after the fight. He's a single target assasin so you cant do more than bring there strongest carry down as fast as you can in teamfigts.

Farming: just Q the minions and auto attack them, Every 10 seconds (if not attacking) nocturnes passive atcivates and it transforms nocturnes auto attack into a AOE auto attack and heals him for a amount of health (only 1 auto attack, so use it wisley)