This Sion build is for a Jungle sion, your start with "cloth armor" and 3 mana potion and 1 heath potion. you start at Wolf at Jungle, after golems (not the buff). at lvl 3 go back to shop and buy "long sword" then go for the golem buff and after lizard (reamber always got "Enrage" on so you get some hp). when you lvl 6 buy "madred's Razor" and go Dragon. after that you can go on your own and kill.
Think this Sion build as a fast leveling sion there got hp for Tanking and damage for kills, try to hold low profile to level 11 where you got "Trinity Force" then you can kill (good idea get "Trinity Force" before boots, then it goes better Jungle)
Hope your will enjoy my build, this is the first build i have made so please say if your need something to know about my sion build.