Hi so this is my 3rd guide this will be not entirely in depth but just a quick look at nocturne and how strong his ganking power is and how much damage he can put out late and early

Start at blue->wolves->wraiths->red

this should be your basic path however if you have a smart/good team get your team to put some damage onto wolves and then leash blues (wolves spawn 1:40 blue 1:55). Now this is where its your choice you can get E and gank straight away from blue or you can get W and clear the jungle and then gank its up to you just make sure always use Q when fighting and E the biggest minion in the camp for the fear

I run pretty standard AD runes i think but the one thing ive got set up is my glyphs (blue) i have it set up so that one is a attack damage which with the other runes boosts your starting game attack damage to +16
but as long as you have some sort of armour and attack damage you will be fine

Again these are up to you as long you get some armour and increased damage to minions. Most people get the smite boost in the defence tree, which is probably very useful but i avoid i prefer my masteries and find that its much more useful

ALWAYS ALWAYS max your Q first highest source of damage early and late, the your W and E are up to you just one thing your W (shield) is used for the shielding of enemy abilities and the passive attack speed, i repeat PASSIVE, if you use it in the jungle your just wasting mana its not going to help in any way with attack speed its a passive ability so its always going to be on. (just ive seen people do this so i felt like i should mention it)

as long as you get smite, get whatever you want, i use flash because i feel safer with the escape exhaust is good for ganking and focusing ad carries or ap caries or just whoever is really fed. Ignite also good but flash or exhaust should be the ones you stick with.

So in conclusion this build and mastery/rune set is pretty much up to you but just have some fun with this the damage you can put out is ridiculous
thanks for reading and hope you find something nice within the darkness that is nocturne :DD