Just because it works like crazy.

Pretty standard here. Smite for jungling and flash for engaging or escaping. You could also pick ghost for ganks but i rarely do that.

Q Ambush: This is your bread and butter when ganking. You should take at lvl 4 for you first gank and max this second or third. I prefer to just max Q and W simultaneously because it gives both abilities a advantage that you need.

W Venom cask: Max this second or third. The slow percentage is increased for every lvl in this skill so thats also good when gankin but your duration of invisibility increases per lvl in your Q skill, so try to max those simultaneously

E Contaminate: This is twitch's best skill in my opinion, it provides crazy jungle clear and insane dmg late game during team fight in combination with your R and your W. This is also why AP/AS twitch works, because of the ap ratio on this and with you attack speed you get stacks of your passive real quick.

R Rat-ta-tat-tat: A great ultimate for teamfight and gankin duo lanes like bottom. Do not use it to clear minions or camps, but if its up use it in a gank. In a teamfight try to hit as much enemies as possible rather than focusing one of them. In that way you can get crazy dmg of with you E.

When jungling you want to start at blue and ask for a leash, after that you should have your W and be able to kill the wolves. Then rush to wraiths and red buff. After that freely kill all jungle camps and gank if necessary or if possible. At lvl 4 you need to gank because you need money for your first item.

Pretty standard jungle start here.
Rush sheen, then spirit item, recurve bow and stinger after.
Go for Nashors tooth as your first big item. Then buy your lich bane and runaan's. Those are two big power spikes. Then buy rabadons deathcap for the AP.

If the enemy team is focused on physical dmg, replace lich bane with iceborn gauntlet. If more magic dmg go for Wits end. If you like statik shiv more than runaan's, feel free to switch. But with runaan's you get more passive stacks so i think thats a better choice. If it really gets out of hand with their AP champions buy spirit visage, but i rarely do this.

For boots Always take berserkers greaves and not sorc boots because twitch has AP ratios, he doesnt do magic damage.

This is my first guide and im just a beginner at mobafire so please dont blame me if its bad just give positive critisism.

Thank you